Summary of Significant Accounting Policies - Goodwill (Detail) $ in Millions	12 Months Ended
Dec. 31, 2015 segment	Oct. 01, 2015 USD ($)
Summary of Significant Accounting Policies
Number of reporting units \| segment	1
Market capitalization in excess net asset value \| $		$ 355.1
Market capitalization in excess net asset value, percentage		76.80%

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

No definition available.

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration