Other Items Impacting Comparability (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Other Income and Expenses [Abstract]
Consulting fees	$ 4,255,000		$ 0	$ 4,255,000	$ 0
Operating tax adjustment	0	$ 2,200,000	0	2,205,000	0
Restructuring charges	$ 0		$ 0	$ (2,574,000)	$ 0