Debt Securities Available-for-Sale - Gross Unrealized Losses On Mortgage-Backed Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ (4,637)	$ (719)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	689,869	242,146
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(466)	(11)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	21,328	459
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	(5,103)	(730)
Debt Securities, Available-for-sale, Unrealized Loss Position	711,197	242,605
U.S. Government agency securities
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(10)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	3,158
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(54)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,290	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	(54)	(10)
Debt Securities, Available-for-sale, Unrealized Loss Position	2,290	3,158
Pass-through certificates \| GSE
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(2,543)	(233)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	417,291	28,419
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(318)	(11)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	14,625	459
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	(2,861)	(244)
Debt Securities, Available-for-sale, Unrealized Loss Position	431,916	28,878
REMICs \| GSE
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1,350)	(476)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	125,725	210,569
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(94)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	4,413	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	(1,444)	(476)
Debt Securities, Available-for-sale, Unrealized Loss Position	130,138	$ 210,569
Other debt securities \| Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(744)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	146,853
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	(744)
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 146,853

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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