Supplemental Schedule of Cash Flow Information - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
Supplemental Cash Flow Elements [Abstract]
Income taxes paid		$ 0	$ 0
Interest paid	$ 7,611,000	$ 16,919,000	$ 38,500,000