FAIR VALUE (Assets and Liabilities Not Measured at Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Assets:
Cash and Restricted cash	$ 1,238,713	$ 620,135	$ 587,306	$ 724,215
Liabilities:
Variable-rate debt	2,438,879	2,229,958
Allowance for doubtful accounts	9,800	15,600
Allowance for notes receivable		200
Level 1 | Carrying Amount
Assets:
Cash and Restricted cash	1,238,713	620,135
Level 1 | Estimated Fair Value
Assets:
Cash and Restricted cash	1,238,713	620,135
Level 3 | Carrying Amount
Assets:
Accounts receivable, net	9,944	12,279
Notes receivable, net	36,000	36,379
Level 3 | Estimated Fair Value
Assets:
Accounts receivable, net	9,944	12,279
Notes receivable, net	36,000	36,379
Level 2 | Carrying Amount
Liabilities:
Fixed-rate debt	1,906,187	1,908,660
Variable-rate debt	2,438,879	2,229,958
Level 2 | Estimated Fair Value
Liabilities:
Fixed-rate debt	1,864,876	1,949,773
Variable-rate debt	$ 2,438,879	$ 2,229,958