Goodwill and Intangible Assets - Schedule of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Balance at beginning of period	$ 41,327	$ 20,786
Acquisition during period	64,994	27,531
Impairment expense		(6,990)
HIE acquisition purchase price allocation adjustments	589
Balance at end of period	$ 105,732	$ 41,327