RELATED PARTY TRANSACTIONS (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
RELATED PARTY TRANSACTIONS
Mortgage loan payments received	$ 749,397,000	$ 1,016,899,000	$ 1,068,552,000
Affiliates
RELATED PARTY TRANSACTIONS
Lease revenues	5,200,000	6,400,000	6,000,000.0
Cost of services	273,100,000	277,700,000	249,300,000
Intercompany payables	46,900,000	50,900,000
Intercompany receivables	12,600,000	8,000,000.0
Certain corporations with which the parent's directors were affiliated
RELATED PARTY TRANSACTIONS
Premiums and policy fees or other amounts for insurance and investment products, interest on bonds and commissions on securities underwriting		6,400,000	6,800,000
Joint Venture
RELATED PARTY TRANSACTIONS
Mortgage loan payments received	4,500,000	23,200,000	6,800,000
Proceeds from collection of principal payments on mortgage loans	15,600,000
Payment of Management Fee \| Affiliates
RELATED PARTY TRANSACTIONS
Management fee for certain services provided	11,800,000	11,100,000	12,200,000
PLC \| Certain corporations with which the parent's directors were affiliated
RELATED PARTY TRANSACTIONS
Commission, interest on debt and investment products and fees		$ 1,900,000	$ 2,300,000
PLC \| Shades Creek \| Agreement to Provide Additional Capital \| Affiliates
RELATED PARTY TRANSACTIONS
Management fee for certain services provided	$ 0

Proceeds Collection Of Principal Payments From Mortgage Notes Receivable

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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The cash inflow from proceeds from sale of receivables arising from the mortgage note on real estate; includes collections on mortgage notes receivable that are not classified as operating cash flows.

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Amount of transactions with related party during the financial reporting period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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