Earnings Per Share - Additional Information (Detail) |
9 Months Ended |
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Sep. 30, 2017 | |
| Class A Common Stock [Member] | |
| Earnings Per Share [Line Items] | |
| Common stock, voting rights | One vote per share |
| Class B Common Stock [Member] | |
| Earnings Per Share [Line Items] | |
| Common stock, voting rights | Ten votes per share |
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- Definition Earnings per share disclosure. No definition available.
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- Definition Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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