Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Beginning balance	$ 274,769	$ 268,043
Goodwill acquired	0	6,726
Ending balance	274,769	274,769	$ 268,043
Finite-Lived Intangible Assets [Abstract]
Gross carrying amount	43,574	43,598
Less: accumulated amortization	31,554	27,999
Net carrying amount	12,020	15,599
Impairment of goodwill	0	0
Amortization Expense [Abstract]
Amortization of intangible assets	3,579	4,042	$ 3,960
Future Amortization Expense [Abstract]
2020	3,000
2021	2,300
2022	1,800
2023	1,400
2024	1,100
Thereafter	2,400
Impairment of intangible assets	$ 0	0
Minimum [Member]
Finite-Lived Intangible Assets [Abstract]
Intangible asset useful life	1 year
Maximum [Member]
Finite-Lived Intangible Assets [Abstract]
Intangible asset useful life	20 years
Core Deposits Intangibles [Member]
Finite-Lived Intangible Assets [Abstract]
Gross carrying amount	$ 8,951	8,975
Less: accumulated amortization	7,988	7,377
Net carrying amount	963	1,598
Identified Intangible Assets [Member]
Finite-Lived Intangible Assets [Abstract]
Gross carrying amount	34,623	34,623
Less: accumulated amortization	23,566	20,622
Net carrying amount	$ 11,057	$ 14,001