Securities Available for Sale - Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortized Cost
Amortized cost, after 1 year through 5 years	$ 1,247,513
Amortized cost, due after 5 years through 10 years	41,080
Amortized cost, due after 10 years	375,397
Amortized Cost	1,663,990	$ 399,668
Fair Value
Fair value, after 1 year through 5 years	1,260,703
Fair value, due after 5 years through 10 years	39,133
Fair value, due after 10 years	320,426
Fair Value	$ 1,620,262	345,702
Weighted-average yield, due after 1 year through 5 years	7.57%
Weighted-average yield, due after 5 years through 10 years	2.36%
Weighted-average yield, due after 10 years	2.91%
Weighted-average yield	5.10%
Senior asset-backed securities related to Structured Program transactions
Amortized Cost
Amortized cost, after 1 year through 5 years	$ 1,165,513
Amortized Cost	1,165,513
Fair Value
Fair value, after 1 year through 5 years	1,176,403
Fair Value	1,176,403
Other asset-backed securities related to Structured Program transactions
Amortized Cost
Amortized cost, after 1 year through 5 years	70,662
Amortized Cost	70,662
Fair Value
Fair value, after 1 year through 5 years	73,393
Fair Value	73,393
U.S. agency securities
Amortized Cost
Amortized cost, after 1 year through 5 years	9,000
Amortized cost, due after 5 years through 10 years	18,848
Amortized cost, due after 10 years	65,604
Amortized Cost	93,452	90,447
Fair Value
Fair value, after 1 year through 5 years	8,746
Fair value, due after 5 years through 10 years	17,545
Fair value, due after 10 years	53,813
Fair Value	80,104	74,394
Mortgage-backed securities
Amortized Cost
Amortized cost, after 1 year through 5 years	1,760
Amortized cost, due after 5 years through 10 years	2,024
Amortized cost, due after 10 years	38,727
Amortized Cost	42,511	26,988
Fair Value
Fair value, after 1 year through 5 years	1,596
Fair value, due after 5 years through 10 years	1,713
Fair value, due after 10 years	33,767
Fair Value	37,076	22,518
Other asset-backed securities
Amortized Cost
Amortized cost, after 1 year through 5 years	421
Amortized cost, due after 5 years through 10 years	14,873
Amortized cost, due after 10 years	11,416
Amortized Cost	26,710	14,959
Fair Value
Fair value, after 1 year through 5 years	423
Fair value, due after 5 years through 10 years	14,842
Fair value, due after 10 years	10,836
Fair Value	26,101	14,203
Municipal securities
Amortized Cost
Amortized cost, after 1 year through 5 years	154
Amortized cost, due after 5 years through 10 years	466
Amortized cost, due after 10 years	2,637
Amortized Cost	3,257	3,277
Fair Value
Fair value, after 1 year through 5 years	139
Fair value, due after 5 years through 10 years	410
Fair value, due after 10 years	2,040
Fair Value	2,589	2,443
U.S. agency residential mortgage-backed securities
Amortized Cost
Amortized cost, after 1 year through 5 years	3
Amortized cost, due after 5 years through 10 years	4,869
Amortized cost, due after 10 years	257,013
Fair Value
Fair value, after 1 year through 5 years	3
Fair value, due after 5 years through 10 years	4,623
Fair value, due after 10 years	219,970
Fair Value	$ 224,596	$ 214,427

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ References

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amortized cost excluding accrued interest, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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