Debt securities average maturity term.

No definition available.

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- Definition

Sale of low yielding securities.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Amount, 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), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of realized gain (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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27357-111563

+ Details

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- Definition

Weighted average yield of 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/2009/role/commonPracticeRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1403
-Paragraph (a)

+ Details

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- Definition

Weighted average yield of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1403
-Paragraph (a)

+ Details

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- Definition

Nominal or face amount on the investment owned.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 10
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6438156&loc=d3e57880-113973

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 10
-Paragraph 1
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6431724&loc=d3e32938-113948

+ Details

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Balance Type:	debit
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- Definition

Amount of cash inflow from sale of 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI https://asc.fasb.org/extlink&oid=124260329&loc=d3e26853-111562

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 11
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3151-108585

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3179-108585

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:

Securities - Additional Information (Detail) - USD ($)	3 Months Ended
Securities - Additional Information (Detail) - USD ($)	Mar. 31, 2023	Mar. 31, 2022	Jan. 10, 2022
Debt Securities, Available-for-Sale [Line Items]
Sale of low yielding securities		$ 226,000,000
Debt securities. average yield percentage		0.16%
Reinvested in debt securities		$ 220,000,000
Reinvested debt securities, average yield percentage		1.86%
Proceeds from sales of available for sale securities	$ 0	$ 222,473,000
Avaliable for sale of debt securities realized gains or losses	$ 0
United States Treasury Notes [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt securities purchased at par value			$ 600,000,000
Debt securities. average yield percentage			1.42%
Debt securities, average maturity term			53 months