Commitments and Contingencies - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Aug. 30, 2013	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Long-term Purchase Commitment [Line Items]
Rent expense		$ 1,200,000	$ 400,000	$ 2,000,000	$ 1,000,000
Lease term	120 months
Recorded assets		96,264,000		96,264,000		$ 88,516,000
Lease financing obligation		43,100,000		43,100,000		43,600,000
Lease financing obligation, current		1,200,000		1,200,000
Lease financing obligations, non-current		41,912,000		41,912,000		42,547,000
Land lease expense		300,000	$ 300,000	600,000
Contract manufacturer liability		200,000		200,000		300,000
Deposits and other assets
Long-term Purchase Commitment [Line Items]
Restricted deposits		2,300,000		2,300,000		2,300,000
Line of Credit | Letter of Credit
Long-term Purchase Commitment [Line Items]
Letter of credit		4,000,000		4,000,000
Building and improvements
Long-term Purchase Commitment [Line Items]
Recorded assets		53,400,000		53,400,000		53,400,000
Land
Long-term Purchase Commitment [Line Items]
Land lease expense					$ 600,000
Building
Long-term Purchase Commitment [Line Items]
Recorded assets		$ 35,154,000		$ 35,154,000		$ 35,154,000
Estimated useful life				30 years