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Borrowings Borrowings - (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Jan. 31, 2022	Oct. 30, 2020	Dec. 16, 2019
Subordinated Notes Due 2029 \| Subordinated Debt \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.53%
Subordinated Notes Due 2030 \| Subordinated Debt \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.69%
Sterling
Debt Instrument [Line Items]
Aggregate principal amount		$ 3,240,535	$ 225,000	$ 274,000
Fixed-to-floating rate			3.875%	4.00%
Long-term debt		516,881
Sterling \| Subordinated Notes Due 2029 \| Subordinated Debt
Debt Instrument [Line Items]
Long-term debt		281,000
Sterling \| Subordinated Notes Due 2030 \| Subordinated Debt
Debt Instrument [Line Items]
Long-term debt		$ 235,900