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v2.4.1.9

Stock Split (Details) | 0 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 05, 2014 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 17, 2014
Class of Stock [Line Items] |  |  |  |
Common stock, shares outstanding (in shares) |  | 295,247,958 us-gaap_CommonStockSharesOutstanding | 291,156,046 us-gaap_CommonStockSharesOutstanding |
Common Stocks |  |  |  |
Class of Stock [Line Items] |  |  |  |
Common stock split conversion ratio | 2 us-gaap_StockholdersEquityNoteStockSplitConversionRatio1 / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember |  |  |
Common stock split, stock dividend percent | 100.00%gntx_StockholdersEquityNoteStockSplitStockDividendPercent / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember |  |  |
Common stock split, additional shares issued for every share held (in shares) |  |  |  | 1 gntx_StockholdersEquityNoteStockSplitAdditionalSharesIssuedforEveryShareHeld / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember
Common stock, shares outstanding (in shares) |  | 295,200,000.0 us-gaap_CommonStockSharesOutstanding / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember |  | 147,600,000.0 us-gaap_CommonStockSharesOutstanding / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember

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- Definition Stockholders' Equity Note, Stock Split, Additional Shares Issued for Every Share Held + References No definition available. + Details
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- Definition Stockholders' Equity Note, Stock Split, Stock Dividend, Percent + References No definition available. + Details
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 + Details
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- Definition Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Stock Split -URI http://asc.fasb.org/extlink&oid=6525746 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB TOPIC 4.C) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770 + Details
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