Investment Securities - Unrealized Loss Positions (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 continuous months	$ 612,985	$ 201,204
Greater than or equal to 12 continuous months	44,628	0
Total Securities in a loss position	657,613	201,204
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 continuous months	(42,663)	(2,867)
Greater than or equal to 12 continuous months	(3,280)	0
Held-to-maturity, gross unrealized losses	(45,943)	(2,867)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	849,125	797,781
Available-for-sale, greater than 12 continuous months, fair value	20,759	14,173
Available-for-sale, total securities in a loss position, fair value	869,884	811,954
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(38,582)	(12,411)
Available-for-sale, greater than 12 continuous months, unrealized loss	(2,477)	(615)
Available-for-sale, total securities in a loss position, unrealized loss	(41,059)	(13,026)
Marketable Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Marketable securities, less than 12 continuous months, fair value	1,462,110	998,985
Marketable securities, greater than 12 continuous months, fair value	65,387	14,173
Marketable securities, total securities in a loss position, fair value	1,527,497	1,013,158
Marketable Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]
Marketable securities, less than 12 continuous months, unrealized loss	(81,245)	(15,278)
Marketable securities, greater than 12 continuous months, unrealized loss	(5,757)	(615)
Marketable securities, total securities in a loss position, unrealized loss	(87,002)	(15,893)
MBS pass-through securities issued by FHLMC, FNMA and GNMA
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 continuous months	299,200	76,619
Greater than or equal to 12 continuous months	0	0
Total Securities in a loss position	299,200	76,619
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 continuous months	(18,528)	(712)
Greater than or equal to 12 continuous months	0	0
Held-to-maturity, gross unrealized losses	(18,528)	(712)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	108,982	263,474
Available-for-sale, greater than 12 continuous months, fair value	0	0
Available-for-sale, total securities in a loss position, fair value	108,982	263,474
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(5,486)	(2,784)
Available-for-sale, greater than 12 continuous months, unrealized loss	0	0
Available-for-sale, total securities in a loss position, unrealized loss	(5,486)	(2,784)
CMOs issued by FHLMC
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 continuous months	165,101	54,811
Greater than or equal to 12 continuous months	4,328	0
Total Securities in a loss position	169,429	54,811
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 continuous months	(11,498)	(1,045)
Greater than or equal to 12 continuous months	(313)	0
Held-to-maturity, gross unrealized losses	(11,811)	(1,045)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	359,856	226,175
Available-for-sale, greater than 12 continuous months, fair value	4,107	4,415
Available-for-sale, total securities in a loss position, fair value	363,963	230,590
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(14,357)	(4,677)
Available-for-sale, greater than 12 continuous months, unrealized loss	(399)	(152)
Available-for-sale, total securities in a loss position, unrealized loss	(14,756)	(4,829)
CMOs issued by FNMA
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 continuous months	25,350
Greater than or equal to 12 continuous months	0
Total Securities in a loss position	25,350
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 continuous months	(1,000)
Greater than or equal to 12 continuous months	0
Held-to-maturity, gross unrealized losses	(1,000)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	40,170	37,348
Available-for-sale, greater than 12 continuous months, fair value	0	0
Available-for-sale, total securities in a loss position, fair value	40,170	37,348
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(2,258)	(611)
Available-for-sale, greater than 12 continuous months, unrealized loss	0	0
Available-for-sale, total securities in a loss position, unrealized loss	(2,258)	(611)
CMOs issued by GNMA
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 continuous months	11,944
Greater than or equal to 12 continuous months	0
Total Securities in a loss position	11,944
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 continuous months	(431)
Greater than or equal to 12 continuous months	0
Held-to-maturity, gross unrealized losses	(431)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	37,732	44,790
Available-for-sale, greater than 12 continuous months, fair value	0	0
Available-for-sale, total securities in a loss position, fair value	37,732	44,790
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(1,725)	(553)
Available-for-sale, greater than 12 continuous months, unrealized loss	0	0
Available-for-sale, total securities in a loss position, unrealized loss	(1,725)	(553)
SBA-backed securities
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 continuous months	3,216
Greater than or equal to 12 continuous months	0
Total Securities in a loss position	3,216
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 continuous months	(29)
Greater than or equal to 12 continuous months	0
Held-to-maturity, gross unrealized losses	(29)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	43,665	7,478
Available-for-sale, greater than 12 continuous months, fair value	1,124	1,209
Available-for-sale, total securities in a loss position, fair value	44,789	8,687
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(1,400)	(112)
Available-for-sale, greater than 12 continuous months, unrealized loss	(44)	(43)
Available-for-sale, total securities in a loss position, unrealized loss	(1,444)	(155)
Debentures of government- sponsored agencies
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 continuous months	65,826	50,571
Greater than or equal to 12 continuous months	40,300	0
Total Securities in a loss position	106,126	50,571
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 continuous months	(6,510)	(901)
Greater than or equal to 12 continuous months	(2,967)	0
Held-to-maturity, gross unrealized losses	(9,477)	(901)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	114,450	148,979
Available-for-sale, greater than 12 continuous months, fair value	7,845	8,549
Available-for-sale, total securities in a loss position, fair value	122,295	157,528
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(5,673)	(2,527)
Available-for-sale, greater than 12 continuous months, unrealized loss	(1,124)	(420)
Available-for-sale, total securities in a loss position, unrealized loss	(6,797)	(2,947)
U.S. Treasury securities
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	10,973	11,629
Available-for-sale, greater than 12 continuous months, fair value	0	0
Available-for-sale, total securities in a loss position, fair value	10,973	11,629
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(917)	(256)
Available-for-sale, greater than 12 continuous months, unrealized loss	0	0
Available-for-sale, total securities in a loss position, unrealized loss	(917)	(256)
Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 continuous months	42,348	19,203
Greater than or equal to 12 continuous months	0	0
Total Securities in a loss position	42,348	19,203
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 continuous months	(4,667)	(209)
Greater than or equal to 12 continuous months	0	0
Held-to-maturity, gross unrealized losses	(4,667)	(209)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	102,115	17,552
Available-for-sale, greater than 12 continuous months, fair value	2,243	0
Available-for-sale, total securities in a loss position, fair value	104,358	17,552
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(5,153)	(381)
Available-for-sale, greater than 12 continuous months, unrealized loss	(361)	0
Available-for-sale, total securities in a loss position, unrealized loss	(5,514)	(381)
Corporate bonds
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	29,421	38,495
Available-for-sale, greater than 12 continuous months, fair value	5,440	0
Available-for-sale, total securities in a loss position, fair value	34,861	38,495
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(1,579)	(506)
Available-for-sale, greater than 12 continuous months, unrealized loss	(549)	0
Available-for-sale, total securities in a loss position, unrealized loss	(2,128)	(506)
Asset-backed securities
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract]
Available-for-sale, less than 12 continuous months, fair value	1,761	1,861
Available-for-sale, greater than 12 continuous months, fair value	0	0
Available-for-sale, total securities in a loss position, fair value	1,761	1,861
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available-for-sale, less than 12 continuous months, unrealized loss	(34)	(4)
Available-for-sale, greater than 12 continuous months, unrealized loss	0	0
Available-for-sale, total securities in a loss position, unrealized loss	$ (34)	$ (4)

Available-for-sale Securities and Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value, Total

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Available-for-sale Securities and Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value

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Available-for-sale Securities and Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value

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Marketable Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for less than 12 months.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for 12 months or longer.

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