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

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

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

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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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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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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.

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

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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) - Subsequent Events [Member] - USD ($) $ / shares in Units, $ in Millions	Feb. 23, 2018	Jan. 16, 2018	Feb. 14, 2018	Jan. 31, 2018
Subsequent Event [Line Items]
Dividend declaration date		Jan. 16, 2018
Common stock dividends per share declared		$ 0.09
Dividend record date		Jan. 31, 2018
Dividend payment date		Feb. 14, 2018
Quarterly dividend payable subsequent to balance sheet date			$ 4.4
Stock repurchased, shares	600,000
Shares repurchased, average price per share	$ 16.18
Additional shares authorized for purchase	2,900,000
Early Retirement Incentive Program [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Estimated liability				$ 3.6
Early Retirement Incentive Program [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Estimated liability				$ 14.3