CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Securities Available-for-Sale, Amortized Cost	$ 1,681,122,000	$ 1,172,175,000
Securities Available-for-Sale, Allowance for Credit Losses	$ 0	$ 0
Common stock, stated value (USD per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	45,000,000	45,000,000

Face amount or stated value per share of common stock.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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- Definition

Amount excluding accrued interest, of allowance for credit loss 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 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Amortized cost excluding accrued interest, before 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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No definition available.

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