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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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 stock repurchase plan authorized.

+ References

No definition available.

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

+ References

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-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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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.

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Equity.

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No definition available.

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Stockholders' Equity - Additional Information (Detail) - USD ($)		3 Months Ended
	Jan. 22, 2018	Mar. 31, 2018	Mar. 31, 2017	Sep. 30, 2017
Equity [Line Items]
Treasury shares acquired		93,000
Dividends per share declared on outstanding common stock	$ 0.14	$ 0.14	$ 0.14
Dividends payable date	Mar. 12, 2018
Dividends payable, shareholders record date	Feb. 28, 2018
September 2017 Share Repurchase Program [Member]
Equity [Line Items]
Treasury shares acquired		92,749
Shares repurchased during period		$ 2,700,000
Maximum [Member] \| September 2017 Share Repurchase Program [Member]
Equity [Line Items]
Amount of shares authorized to repurchase				$ 20,000,000