Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

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Amount, before tax, of other-than-temporary impairment (OTTI) on investment in debt security measured at amortized cost (held-to-maturity), recognized in earnings and other comprehensive income (OCI).

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Securities Held-to-Maturity - Rollforward of Allowance (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Changes in the allowance for credit losses
Allowance for credit loss, Beginning balance	$ 2,022		$ 1,753
Provision for credit loss expense/(reversal)	68		337
Allowance for credit loss, Ending balance	2,090		2,090
Impairment of held-to maturity securities			0
Held-to-Maturity Securities
Changes in the allowance for credit losses
Interest income (including the amortization of discount)	3,700	$ 3,400	13,900	$ 9,400
APL certificates
Changes in the allowance for credit losses
Allowance for credit loss, Beginning balance	1,756		1,422
Provision for credit loss expense/(reversal)	47		381
Allowance for credit loss, Ending balance	1,803		1,803
B Piece bonds
Changes in the allowance for credit losses
Allowance for credit loss, Beginning balance	266		331
Provision for credit loss expense/(reversal)	21		(44)
Allowance for credit loss, Ending balance	$ 287		$ 287