Value of shares of common stock repurchased under the stock repurchase program over the life of the plan to date.

No definition available.

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- Definition

Number of shares of common stock repurchased under the stock repurchase program over the life of the plan to date.

+ References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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- Definition

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

+ References

+ Details

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- Definition

The month and year (YYYY-MM) that the dividend to be paid was declared.

+ 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.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
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-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended	3 Months Ended
	Apr. 30, 2018	Mar. 31, 2018	Mar. 31, 2017	Feb. 28, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend declared and paid per share		$ 0.20	$ 0.19
Aggregate dividend declared for the year		$ 3,600,000	$ 3,500,000
Dividend declared per share		$ 0.20	$ 0.19
Authorized to purchase of common stock under the stock repurchase program		$ 535,000,000		$ 50,000,000
Repurchase of common Stock		0.1	0.6
Cumulative aggregate cost of repurchase of common stock		$ 4,400,000	$ 21,500,000
Cumulative repurchase of common stock		16.2
Aggregate cost of repurchase of common stock		$ 469,300,000
Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend declared per share	$ 0.20
Dividend payable, date declared	2018-04
Dividend declared payable date	Jun. 27, 2018
Dividend payable, record date	Jun. 13, 2018