Subsequent Events - Additional Information (Detail) (Dividend Declared [Member], USD $)	3 Months Ended
Mar. 31, 2015	Apr. 28, 2015
Subsequent Event [Line Items]
Date of payment to shareholders entitled to dividends	Jun. 26, 2015
Date of record of shareholders entitled to dividends	Jun. 12, 2015
Subsequent Event [Member]
Subsequent Event [Line Items]
Cash dividend per share		$ 0.15

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

+ Details

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Data Type:	xbrli:dateItemType
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Period Type:	duration

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
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