Stockholders' Equity - Cash Dividends Declared to Stockholders (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Declaration date	Apr. 29, 2015
Record Date	May 22, 2015
Payment Date	Jun. 25, 2015
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Per Share Amount	0.125
Total Payment	2,715
Common Stock [Member] \| Installment One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Declaration date	Mar. 04, 2015
Record Date	Mar. 18, 2015
Payment Date	Mar. 30, 2015
Per Share Amount	0.125
Total Payment	2,715

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 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.

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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

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