Stockholders' Equity - Cash Dividends Declared to Stockholders (Detail) (Common Stock [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Per Share Amount	$ 0.375
Total Payment	$ 8,121
Installment One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Declaration date	Mar. 05, 2014
Record Date	Mar. 18, 2014
Payment Date	Mar. 28, 2014
Per Share Amount	$ 0.125
Total Payment	2,707
Installment Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Declaration date	Apr. 30, 2014
Record Date	May 22, 2014
Payment Date	Jun. 25, 2014
Per Share Amount	$ 0.125
Total Payment	2,707
Installment Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Declaration date	Jul. 30, 2014
Record Date	Aug. 19, 2014
Payment Date	Sep. 10, 2014
Per Share Amount	$ 0.125
Total Payment	$ 2,707

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

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

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

+ 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

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

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- Definition

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

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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.

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