Securities Available for Sale - Continuous loss (Details) $ in Thousands	Sep. 30, 2021 USD ($) position	Dec. 31, 2020 USD ($) position
Schedule of Securities Available-for-sale [Line Items]
Fair Value, Less than 12 months	$ 149,607	$ 26,678
Unrealized Losses, Less than 12 months	(2,892)	(855)
Fair Value, 12 months or longer	1,583	6,052
Unrealized Losses, 12 months or longer	(16)	(118)
Fair Value	151,190	32,730
Unrealized Losses	$ (2,908)	$ (973)
Number of positions with unrealized losses \| position	118	55
U.S. agency residential mortgage-backed securities
Schedule of Securities Available-for-sale [Line Items]
Fair Value, Less than 12 months	$ 100,063
Unrealized Losses, Less than 12 months	(1,877)
Fair Value, 12 months or longer	0
Unrealized Losses, 12 months or longer	0
Fair Value	100,063
Unrealized Losses	(1,877)
Asset-backed securities related to Structured Program transactions
Schedule of Securities Available-for-sale [Line Items]
Fair Value, Less than 12 months	0	$ 26,678
Unrealized Losses, Less than 12 months	0	(855)
Fair Value, 12 months or longer	1,583	6,052
Unrealized Losses, 12 months or longer	(16)	(118)
Fair Value	1,583	32,730
Unrealized Losses	(16)	$ (973)
Other asset-backed securities
Schedule of Securities Available-for-sale [Line Items]
Fair Value, Less than 12 months	6,142
Unrealized Losses, Less than 12 months	(40)
Fair Value, 12 months or longer	0
Unrealized Losses, 12 months or longer	0
Fair Value	6,142
Unrealized Losses	(40)
Commercial mortgage-backed securities
Schedule of Securities Available-for-sale [Line Items]
Fair Value, Less than 12 months	25,783
Unrealized Losses, Less than 12 months	(367)
Fair Value, 12 months or longer	0
Unrealized Losses, 12 months or longer	0
Fair Value	25,783
Unrealized Losses	(367)
U.S. agency securities
Schedule of Securities Available-for-sale [Line Items]
Fair Value, Less than 12 months	14,377
Unrealized Losses, Less than 12 months	(548)
Fair Value, 12 months or longer	0
Unrealized Losses, 12 months or longer	0
Fair Value	14,377
Unrealized Losses	(548)
Municipal securities
Schedule of Securities Available-for-sale [Line Items]
Fair Value, Less than 12 months	3,242
Unrealized Losses, Less than 12 months	(60)
Fair Value, 12 months or longer	0
Unrealized Losses, 12 months or longer	0
Fair Value	3,242
Unrealized Losses	$ (60)

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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