Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Income Tax Contingency [Line Items]
Investment Tax Credit	$ 4,200,000	$ 2,400,000
Tax Credit Carryforward, Expiration Date	2028
Tax benefit realized upon settlement	50.00%
Unrecognized Tax Benefits	$ 1,525,000	0
Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued	300,000	0
Federal
Income Tax Contingency [Line Items]
Net operating loss carryforwards	$ 595,000,000	454,500,000
Net operating loss carryforwards, Year of expiration	2028
California
Income Tax Contingency [Line Items]
Net operating loss carryforwards	$ 368,000,000	283,100,000
Net operating loss carryforwards, Year of expiration	2020
Other State
Income Tax Contingency [Line Items]
Net operating loss carryforwards	$ 178,600,000	126,500,000
Net operating loss carryforwards, Year of expiration	2020
California Enterprise Zone Credits.
Income Tax Contingency [Line Items]
Investment Tax Credit	$ 1,000,000	900,000
Tax Credit Carryforward, Expiration Date	2023
Windfall Stock Option | Federal
Income Tax Contingency [Line Items]
Net operating loss carryforwards	$ 5,300,000	1,800,000
Windfall Stock Option | California
Income Tax Contingency [Line Items]
Net operating loss carryforwards	1,300,000	1,100,000
Windfall Stock Option | Other State
Income Tax Contingency [Line Items]
Net operating loss carryforwards	$ 2,500,000	$ 500,000