Stockholders' Equity - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
Apr. 30, 2017	Mar. 31, 2017	Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend declared and paid per share		$ 0.19	$ 0.18
Aggregate dividend declared for the year		$ 3,500,000	$ 3,200,000
Dividend declared per share		$ 0.19	$ 0.18
Authorized to purchase of common stock under the stock repurchase program		$ 485,000,000
Repurchase of common Stock		600,000	0
Cumulative aggregate cost of repurchase of common stock		$ 21,500,000
Cumulative repurchase of common stock		15,600,000
Aggregate cost of repurchase of common stock		$ 446,400,000
Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend declared per share	$ 0.19
Dividend payable, date declared	Jun. 21, 2017
Dividend payable, record date	Jun. 07, 2017

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

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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.

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- Definition

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

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- Definition

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

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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

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- Definition

Date the dividend to be paid was declared, 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=6367179&loc=d3e4304-108586

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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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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.

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No definition available.

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- Definition

Amount of stock repurchase plan authorized.

+ References

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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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- 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
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-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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