Investment Securities - Schedule of AFS Debt Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	$ 2,808,862	$ 318,953
Less Than 12 Months, Gross Unrealized Losses	(56,121)	(1,499)
12 Months or Longer, Fair Value	317,559	165,159
12 Months or Longer, Gross Unrealized Losses	(10,167)	(876)
Total Fair Value	3,126,421	484,112
Total Gross Unrealized Losses	(66,288)	(2,375)
Debt Securities Issued by the U.S. Treasury and Government Agencies
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	51,455	21,338
Less Than 12 Months, Gross Unrealized Losses	(195)	(42)
12 Months or Longer, Fair Value	9,995	87,070
12 Months or Longer, Gross Unrealized Losses	(89)	(549)
Total Fair Value	61,450	108,408
Total Gross Unrealized Losses	(284)	(591)
Debt Securities Issued by States and Political Subdivisions
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	643
Less Than 12 Months, Gross Unrealized Losses	(5)
12 Months or Longer, Fair Value		26
12 Months or Longer, Gross Unrealized Losses		(1)
Total Fair Value	643	26
Total Gross Unrealized Losses	(5)	(1)
Debt Securities Issued by Government-Sponsored Enterprises
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	814
Less Than 12 Months, Gross Unrealized Losses	(10)
12 Months or Longer, Fair Value	49
12 Months or Longer, Gross Unrealized Losses	(1)
Total Fair Value	863
Total Gross Unrealized Losses	(11)
Debt Securities Issued by Corporations
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	249,629	65,000
Less Than 12 Months, Gross Unrealized Losses	(2,846)	(853)
12 Months or Longer, Fair Value	64,029	50,000
12 Months or Longer, Gross Unrealized Losses	(970)	(103)
Total Fair Value	313,658	115,000
Total Gross Unrealized Losses	(3,816)	(956)
Residential - Government Agencies
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	810,157	113,538
Less Than 12 Months, Gross Unrealized Losses	(17,131)	(222)
12 Months or Longer, Fair Value	41,471	28,063
12 Months or Longer, Gross Unrealized Losses	(1,635)	(223)
Total Fair Value	851,628	141,601
Total Gross Unrealized Losses	(18,766)	(445)
Residential - U.S. Government-Sponsored Enterprises
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	1,670,500	94,002
Less Than 12 Months, Gross Unrealized Losses	(35,711)	(324)
12 Months or Longer, Fair Value	180,205
12 Months or Longer, Gross Unrealized Losses	(6,536)
Total Fair Value	1,850,705	94,002
Total Gross Unrealized Losses	(42,247)	(324)
Commercial - Government Agencies
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	25,664	25,075
Less Than 12 Months, Gross Unrealized Losses	(223)	(58)
12 Months or Longer, Fair Value	21,810
12 Months or Longer, Gross Unrealized Losses	(936)
Total Fair Value	47,474	25,075
Total Gross Unrealized Losses	(1,159)	(58)
Mortgage-Backed Securities
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	2,506,321	232,615
Less Than 12 Months, Gross Unrealized Losses	(53,065)	(604)
12 Months or Longer, Fair Value	243,486	28,063
12 Months or Longer, Gross Unrealized Losses	(9,107)	(223)
Total Fair Value	2,749,807	260,678
Total Gross Unrealized Losses	$ (62,172)	$ (827)

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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