Income Taxes - Unrecognized Tax Benefits - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 135,000	$ 135,000	$ 0	$ 10,547,000
Unrecognized tax benefits that, if recognized, would affect the effective tax rate	0	0	0
Interest expense (benefit) on unrecognized income tax benefits	0	0	$ 500,000
Interest on income taxes accrued	$ 0	$ 0