Loans Receivable - Summary of Real Estate Loan Activity (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Advances on loans receivable:
Net cash advances on loans receivable	$ 953,006	$ 216,307
Receipts on loans receivable:
Net cash receipts on loans receivable	250,415	14,345
Seniors Housing Operating
Advances on loans receivable:
Investments in new loans	935,594	194,942
Draws on existing loans	17,412	21,365
Net cash advances on loans receivable	953,006	216,307
Receipts on loans receivable:
Loan payoffs	179,827	0
Principal payments on loans	70,588	14,345
Net cash receipts on loans receivable	250,415	14,345
Net cash advances (receipts) on loans receivable	$ 702,591	$ 201,962

The net amount paid or received by the reporting entity associated with purchase (sale or collection) of loans receivable arising from the financing of goods and services.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The cash outflow for the purchase of loan receivable arising from the financing of goods and services.

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The cash inflow associated with the collection, including prepayments, of loans receivable issued for financing of goods and services.

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Advances on real estate loans receivable.

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Draws on existing loans.

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Investments in new loans.

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Loan payoffs.

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Principal payments on loans.

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Receipts on real estate loans receivable.

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