Number of shares of common stock repurchased under the stock repurchase program during the period.

No definition available.

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- Definition

Value 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

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

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- Definition

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

+ References

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: 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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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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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- 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

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: 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=6928386&loc=d3e21463-112644

Reference 3: 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

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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Stockholders' Equity - Additional Information (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended						9 Months Ended			1 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2014	Sep. 30, 2013	Apr. 30, 2014	Oct. 31, 2014 Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend declared and paid per share	$ 0.16	$ 0.16	$ 0.16	$ 0.15	$ 0.15	$ 0.15
Aggregate dividend declared for the year							$ 9,100,000	$ 9,400,000
Dividend declared per share	$ 0.16			$ 0.15			$ 0.48	$ 0.45		$ 0.16
Dividend payable date										Dec. 17, 2014
Dividend payable record date										Dec. 03, 2014
Authorized to purchase of common stock under the stock repurchase program	410,000,000						410,000,000		25,000,000
Repurchase of common Stock							1.8
Cumulative aggregate cost of repurchase of common stock							66,600,000
Cumulative repurchase of common stock	14.2						14.2
Aggregate cost of repurchase of common stock							$ 395,600,000