Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Jul. 17, 2018	Aug. 15, 2018
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	Jul. 17, 2018
Common stock dividends per share declared	$ 0.09
Dividend record date	Aug. 01, 2018
Dividend payment date	Aug. 15, 2018

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.

+ References

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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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- 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.

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