Commitments and Contingencies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 12, 2012	May 13, 2011	May 12, 2011
Commitments and Contingencies Disclosure [Line Items]
Irrevocable letter of credit delivered as a security for lease obligation					$ 2,400,000
Letter of credit amount				2,600,000		2,600,000
Irrevocable letter of credit, additional amount for potential market fluctuation				200,000
Restricted Cash and Cash Equivalents	525,000	0
Rent expense	3,033,000	2,931,000	2,912,000
Future minimum lease payments under non-cancelable operating leases
2015	3,368,000
2016	2,892,000
2017	2,793,000
2018	2,900,000
2019	2,748,000
Thereafter	6,813,000
Total	21,514,000
On the fifth anniversary of the lease commencement date
Commitments and Contingencies Disclosure [Line Items]
Irrevocable letter of credit delivered as a security for lease obligation					1,200,000
Two Bright Lights, Inc.
Commitments and Contingencies Disclosure [Line Items]
Restricted Cash and Cash Equivalents	$ 525,000