Income Taxes - Summary of Information Related to Interest and Penalties on Uncertain Tax Positions (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Interest expense	$ 0.1	$ 0.1
Penalties	0.0	$ 0.0
Accrued interest payable	$ 0.7		$ 0.6

No definition available.

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- Definition

Amount of expense for penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

+ Details

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- Definition

Amount of interest expense accrued for an underpayment of income taxes.

+ References

+ Details

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- Definition

Amount of interest expense for an underpayment of income taxes.

+ References

+ Details

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