Derivative Financial Instruments (Summary of Interest Rate Derivatives) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022
Derivative Assets
Derivative Assets	$ 294,748	$ 296,848	$ 183,925
Derivative Liabilities
Gross Amounts Recognized	391,172	338,078	167,857
Interest rate contract
Derivative Assets
Derivative Assets	279,614	286,438	175,756
Less: Amounts offset in the Statements of Condition	0	0	0
Net amount presented in the Statements of Condition	279,614	286,438	175,756
Offsetting Derivative Positions	(125,159)	(64,100)	(6,009)
Collateral Posted	(145,735)	(194,666)	(163,412)
Net Credit Exposure	8,720	27,672	6,335
Derivative Liabilities
Gross Amounts Recognized	382,413	329,307	165,107
Less: Amounts offset in the Statements of Condition	0	0	0
Net amount presented in the Statements of Condition	382,413	329,307	165,107
Offsetting Derivative Positions	(125,159)	(64,100)	(6,009)
Collateral Posted	0	0	(91)
Net Credit Exposure	$ 257,254	$ 265,207	$ 159,007