Investment Operations Impaired Mortgage Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Impaired mortgage loans, Unpaid Principal Balance	$ 4,632	$ 18,622
Financing Receivable, Allowance for Credit Loss	329	3,107	$ 497
Impaired mortgage loans, Related Allowance	$ 4,303	$ 15,515

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Balance Type:	credit
Period Type:	instant

- 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.

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

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-Publisher FASB
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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

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