Investment Securities - Realized Gains and Losses on Securities Available-for-Sale (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Amortized cost of securities sold	$ 440,445	$ 76,184	$ 1,039,965	$ 120,735
Gross realized gains	3,226	517	5,960	618
Gross realized losses	(3,140)	(2)	(6,979)	(2)
Net realized gains (losses)	$ 86	$ 515	$ (1,019)	$ 616

Available For Sale Investment Securities, Sold At Amortized Cost

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- Definition

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
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Amount of realized loss on 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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Amount of realized and unrealized gain (loss) on investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 10
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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-03.7(c),9(a))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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-Publisher FASB
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-Section 45
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