Legal Proceedings and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended
Apr. 16, 2013
Commitments And Contingencies Disclosure [Abstract]
Litigation settlement receivable amount	$ 3.4
Litigation settlement receivable net of litigation expenses	2.1
Litigation settlement expenses	$ 0.3

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

+ Details

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- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

+ Details

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- Definition

Return of or reimbursements received in relation to direct costs and expenses previously paid or incurred.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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