Commitments and Contingencies - Additional Information (Detail) $ in Millions	6 Months Ended
Jun. 30, 2015 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Litigation settlement against the company	$ (2.9)

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

No definition available.

Name:	us-gaap_LitigationSettlementAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration