Mortgage Loans - Allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan credit losses, beginning of period	$ (1,960)	$ (1,164)
Beginning period adjustment for CECL	(10,156)	0
Provision for credit losses on mortgage loans	2,122	154
Change to allowance for loan credit losses	(1,898)	0
Allowance for loan credit losses, end of period	$ (16,136)	$ (1,318)

Amount of other addition (reduction) in allowance reserve for credit loss.

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- Definition

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

+ References

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- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable.

+ References

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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 related to estimated loss from loan and lease transactions.

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