Goodwill and Intangible Assets - Summary of Intangible Assets (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019 USD ($)
Finite-lived Intangible Assets [Roll Forward]
Core deposit intangible, net, end of period	$ 27,626
Core deposit
Finite-lived Intangible Assets [Roll Forward]
Gross core deposit intangible, beginning of period	20,574
Additions from acquisition	23,066
Gross core deposit intangible, end of period	43,640
Accumulated amortization	(16,014)
Core deposit intangible, net, end of period	$ 27,626