Aggregate dividends declared during the period for each share of common stock outstanding.

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 230
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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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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.

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No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 505
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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Feb. 24, 2017	Jan. 17, 2017	Dec. 31, 2016	Feb. 16, 2017
Subsequent Event [Line Items]
Dividend declaration date			Jan. 17, 2017
Dividend record date			Feb. 02, 2017
Dividend payment date			Feb. 16, 2017
Scenario Forecast [Member]
Subsequent Event [Line Items]
Stock repurchased, shares	200,000
Shares repurchased, average price per share	$ 21.46
Additional shares authorized for purchase	4,200,000
Subsequent Events [Member]
Subsequent Event [Line Items]
Common stock dividends per share declared		$ 0.09
Quarterly dividend payable subsequent to balance sheet date				$ 4.4