Loans Loans - Internal Credit Assessment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	$ 2,950,160	$ 2,919,981
Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	9,774	6,164
Consumer Portfolio
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	507,660	633,464
Consumer Portfolio | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	506,541	632,670
Consumer Portfolio | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	1,119	794
Consumer Portfolio | Residential mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	203,041	313,849
Consumer Portfolio | Residential mortgage | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	201,956	313,088
Consumer Portfolio | Residential mortgage | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	1,085	761
Consumer Portfolio | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	22,169	24,306
Consumer Portfolio | Home equity | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	22,169	24,306
Consumer Portfolio | Home equity | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	0	0
Consumer Portfolio | Other consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	282,450	295,309
Consumer Portfolio | Other consumer | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	282,416	295,276
Consumer Portfolio | Other consumer | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans Receivable	$ 34	$ 33