Goodwill and Intangible Assets - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of Intangible Assets	$ 9,839,000	$ 3,439,000	$ 21,361,000	$ 6,791,000
Goodwill	$ 59,679,000		$ 59,679,000		$ 14,254,000	$ 3,413,000