Loans and Allowance for Credit Losses Loans Modified Under Troubled Debt Restructurings (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total Accruing Troubled Debt Restructurings	$ 52,000	$ 68,426
Non-accrual TDRs (1)	60,504	35,755
Total TDRs	112,504	104,181
Real estate - commercial mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total Accruing Troubled Debt Restructurings	14,651	28,451
Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total Accruing Troubled Debt Restructurings	6,765	6,982
Residential Mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total Accruing Troubled Debt Restructurings	16,861	18,602
Real-estate - home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total Accruing Troubled Debt Restructurings	13,566	14,391
Construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total Accruing Troubled Debt Restructurings	153	0
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total Accruing Troubled Debt Restructurings	$ 4	$ 0