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.

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

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Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions			9 Months Ended
	Nov. 06, 2018	Oct. 16, 2018	Sep. 30, 2018	Nov. 14, 2018
Subsequent Event [Line Items]
Stock repurchased, shares			900,000
Shares repurchased, average price per share			$ 15.75
Additional shares authorized for purchase			2,700,000
Scenario Forecast [Member]
Subsequent Event [Line Items]
Quarterly dividend payable subsequent to balance sheet date				$ 4.3
Subsequent Events [Member]
Subsequent Event [Line Items]
Dividend declaration date		Oct. 16, 2018
Common stock dividends per share declared		$ 0.09
Dividend record date		Oct. 31, 2018
Dividend payment date		Nov. 14, 2018
Stock repurchased, shares	100,000
Shares repurchased, average price per share	$ 13.60
Additional shares authorized for purchase	2,600,000