Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions |
1 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
Jan. 01, 2016 |
Feb. 26, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Subsequent Event [Line Items] | |||||
| Stock repurchased, value | $ 34,483,000 | $ 53,046,000 | $ 17,067,000 | ||
| Dividends declared per common share | $ 0.11 | $ 0.10 | $ 0.10 | ||
| Subsequent Event [Member] | |||||
| Subsequent Event [Line Items] | |||||
| Dividends declared per common share | $ 0.05 | ||||
| Dividends payable, date of record | Mar. 15, 2016 | ||||
| Dividends payable date | Apr. 15, 2016 | ||||
| Common Class A [Member] | |||||
| Subsequent Event [Line Items] | |||||
| Remaining repurchase authorization amount | $ 45,000,000 | ||||
| Common Class A [Member] | Subsequent Event [Member] | |||||
| Subsequent Event [Line Items] | |||||
| Additional authorized amount on repurchase of shares | $ 100,000,000 | ||||
| Remaining repurchase authorization amount | $ 145,000,000 | $ 73,000,000 | |||
| Stock repurchased, shares | 4.0 | ||||
| Stock repurchased, value | $ 72,000,000 | ||||
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- Definition Stock repurchase program additional authorized amount. No definition available.
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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Date the declared dividend will be paid, in CCYY-MM-DD format. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format. No definition available.
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- Definition Amount remaining of a stock repurchase plan authorized. No definition available.
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. No definition available.
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- Definition Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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