Allowance for Credit Losses - Investments in Loans Considered to be Impaired and Related Information on Impaired Loans (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Recorded Investment
Total with a Related Allowance Recorded	$ 23,510
Total without a Related Allowance Recorded	51,827
Total	75,337
Unpaid Principal Balance
Total with a Related Allowance Recorded	24,821
Total without a Related Allowance Recorded	61,950
Total	86,771
Impaired financing receivable, Related Allowance	2,200
Average Recorded Investment
Total with a Related Allowance Recorded	24,655
Total without a Related Allowance Recorded	51,332
Total	75,987
Interest Income Recognized
Total with a Related Allowance Recorded	577
Total without a Related Allowance Recorded	1,839
Total	2,416
Commercial real estate | Commercial
Recorded Investment
Total with a Related Allowance Recorded	13,011
Total without a Related Allowance Recorded	34,909
Total	47,920
Unpaid Principal Balance
Total with a Related Allowance Recorded	14,322
Total without a Related Allowance Recorded	40,201
Total	54,523
Impaired financing receivable, Related Allowance	2,023
Average Recorded Investment
Total with a Related Allowance Recorded	14,018
Total without a Related Allowance Recorded	35,739
Total	49,757
Interest Income Recognized
Total with a Related Allowance Recorded	0
Total without a Related Allowance Recorded	943
Total	943
Commercial and industrial | Commercial
Recorded Investment
Total with a Related Allowance Recorded	10,001
Total without a Related Allowance Recorded	7,605
Total	17,606
Unpaid Principal Balance
Total with a Related Allowance Recorded	10,001
Total without a Related Allowance Recorded	10,358
Total	20,359
Impaired financing receivable, Related Allowance	55
Average Recorded Investment
Total with a Related Allowance Recorded	10,135
Total without a Related Allowance Recorded	5,565
Total	15,700
Interest Income Recognized
Total with a Related Allowance Recorded	576
Total without a Related Allowance Recorded	368
Total	944
Other Consumer | Commercial
Recorded Investment
Total with a Related Allowance Recorded	489
Total without a Related Allowance Recorded	1,425
Total	1,914
Unpaid Principal Balance
Total with a Related Allowance Recorded	489
Total without a Related Allowance Recorded	2,935
Total	3,424
Impaired financing receivable, Related Allowance	113
Average Recorded Investment
Total with a Related Allowance Recorded	489
Total without a Related Allowance Recorded	1,831
Total	2,320
Interest Income Recognized
Total with a Related Allowance Recorded	0
Total without a Related Allowance Recorded	131
Total	131
Consumer real estate | Consumer
Recorded Investment
Total with a Related Allowance Recorded	0
Total without a Related Allowance Recorded	7,884
Total	7,884
Unpaid Principal Balance
Total with a Related Allowance Recorded	0
Total without a Related Allowance Recorded	8,445
Total	8,445
Impaired financing receivable, Related Allowance	0
Average Recorded Investment
Total with a Related Allowance Recorded	0
Total without a Related Allowance Recorded	8,190
Total	8,190
Interest Income Recognized
Total with a Related Allowance Recorded	0
Total without a Related Allowance Recorded	397
Total	397
Other consumer | Consumer
Recorded Investment
Total with a Related Allowance Recorded	9
Total without a Related Allowance Recorded	4
Total	13
Unpaid Principal Balance
Total with a Related Allowance Recorded	9
Total without a Related Allowance Recorded	11
Total	20
Impaired financing receivable, Related Allowance	9
Average Recorded Investment
Total with a Related Allowance Recorded	13
Total without a Related Allowance Recorded	7
Total	20
Interest Income Recognized
Total with a Related Allowance Recorded	1
Total without a Related Allowance Recorded	0
Total	$ 1