Investments (Unrealized Gross Losses and Estimated Fair values of Investment Securities by Length of Time that Individual Securities in Each Category in Continuous Loss Position) (Details) $ in Thousands	Dec. 31, 2022 USD ($) security	Dec. 31, 2021 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | security	335	180
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 215,593	$ 871,583
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	16,957	14,074
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	457,955	101,074
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	84,273	3,656
Debt Securities, Available-for-sale, Unrealized Loss Position	673,548	972,657
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 101,230	$ 17,730
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | security	83
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 42,276
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	463
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Debt Securities, Available-for-sale, Unrealized Loss Position	42,276
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 463
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | security	175	113
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 118,290	$ 659,851
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	11,521	8,999
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	381,355	61,978
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	73,436	2,469
Debt Securities, Available-for-sale, Unrealized Loss Position	499,645	721,829
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 84,957	$ 11,468
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | security	64	56
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 47,340	$ 191,456
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	4,589	4,602
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	62,007	38,117
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	8,824	1,165
Debt Securities, Available-for-sale, Unrealized Loss Position	109,347	229,573
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 13,413	$ 5,767
Subordinated corporate bonds
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | security	13	7
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 7,687	$ 11,932
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	384	232
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	14,593	979
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	2,013	22
Debt Securities, Available-for-sale, Unrealized Loss Position	22,280	12,911
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 2,397	$ 254
Obligations of U.S. government-sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | security		4
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months		$ 8,344
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		241
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer		0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0
Debt Securities, Available-for-sale, Unrealized Loss Position		8,344
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss		$ 241