| 2020-04-30           | 
                                                                                        Quarterly Filings           | 
                                                                                        10-Q           | 
                                                                                        Quarterly report which provides a continuing view of a company's financial position           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        LITTLE WILLIAM G           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        Funk Andrea J.           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        HAGGE STEPHEN J           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        Sweitzer Caesar F           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        CONWAY JOHN W           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        URKIEL WILLIAM S           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        LOLIGER HANS J           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        FEARON RICHARD H           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        TURNER JIM L           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        Lee Rose           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        Muller Josef M           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        MILLER JAMES H           | 
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                                                                                        | 2020-04-29           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        OWENS B CRAIG           | 
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                                                                                        | 2020-04-28           | 
                                                                                        Current Reports           | 
                                                                                        8-K           | 
                                                                                        Report of unscheduled material events or corporate event           | 
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                                                                                        | 2020-04-20           | 
                                                                                        Current Reports           | 
                                                                                        8-K           | 
                                                                                        Report of unscheduled material events or corporate event           | 
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                                                                                        | 2020-04-09           | 
                                                                                        Other           | 
                                                                                        SC 13G/A           | 
                                                                                        An amendment to the SC 13G filing           | 
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                                                                                        | 2020-04-06           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        Sourisseau Didier           | 
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                                                                                        | 2020-04-06           | 
                                                                                        3,4,5           | 
                                                                                        4           | 
                                                                                        Statement of changes in beneficial ownership of securities           | 
                                                                                        Gifford Gerard H           | 
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                                                                                        | 2020-03-30           | 
                                                                                        Proxy Filings           | 
                                                                                        DEFA14A           | 
                                                                                        Additional proxy soliciting materials - definitive           | 
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