Loans Receivable (Narrative) (Details)	12 Months Ended
Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loan loss charge	$ 18,690,000	$ 0	$ 62,966,000
Provision for loan losses	18,690,000	0	62,966,000
Allowance for loan losses	$ 68,372,000	$ 68,372,000	68,372,000	$ 6,563,000
Number of real estate loans on non-accrual status \| loan	1
Real estate loans with outstanding balances	$ 2,534,000
Genesis Healthcare Loans \| Triple-net
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loan loss charge	$ 0		$ 62,966,000	$ 6,935,000

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
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Amount of expense related to estimated loss from loan and lease transactions.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
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Real estate loans with outstanding balances.

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