Equity Compensation Plans - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Pre-tax compensation expense for unvested stock-based compensation grants	$ 3,900
Service period applicable to the grantees on a weighted-average basis, years	1 year 7 months 6 days
RSUs vested and settled in shares of common stock, amount	$ 99	$ 1,260

The total fair value of restricted stock units for which the grantee gained the right during the period, by satisfying service requirements, to receive common shares in accordance with the terms of the arrangement.

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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