The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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Amount of expense related to estimated loss from loan and lease transactions.

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Real Estate Loans Receivable - Narrative (Details) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Mar. 31, 2019 USD ($) loan	Mar. 31, 2019 USD ($) loan	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Financing Receivable, Modifications [Line Items]
Provision for loan losses	$ 18,690	$ 18,690	$ 0
Allowance for loan losses	$ 87,062	$ 87,062	$ 68,372
Number of real estate loans on non-accrual status \| loan	3	3
Real estate loans with outstanding balances	$ 21,224	$ 21,224
Triple-net \| Genesis Healthcare Loans
Financing Receivable, Modifications [Line Items]
Loan loss charge				$ 62,966	$ 6,935