Stockholders' Equity - Cash Dividends Declared to Stockholders (Detail) - Jun. 30, 2015 - USD ($) $ / shares in Units, $ in Thousands	Total
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Declaration Date	Jul. 28, 2015
Record Date	Aug. 19, 2015
Payment Date	Sep. 10, 2015
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Per Share Amount	$ 0.125
Total Payment	$ 5,428
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
Common Stock [Member] \| 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	$ 2,713

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

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

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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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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