Commercial Mortgage Loans - Loans Receivable by Class (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan	Jan. 01, 2020 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Senior loans	$ 2,653,564	$ 2,721,325
Mezzanine loans	9,117	41,638
Total gross carrying value of loans	2,662,681	2,762,963
Allowance for loan losses	21,702	921
Total commercial mortgage loans, held for investment, net	$ 2,640,979	$ 2,762,042	$ 2,762,042
Commercial Mortgage Receivable, Held-For-Investment
Financing Receivable, Credit Quality Indicator [Line Items]
Number of mezzanine loans funded \| loan	118	122

Loans Receivable, Gross, Credit Loans

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Number of Mezzanine Loans Funded

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Senior Loans, Receivable

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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

+ References

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