UNCONSOLIDATED AFFILIATES - Summarized Financial Information (Parenthetical) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Equity Method Investments [Line Items]
Equity in earnings (losses) of unconsolidated affiliates	$ (14,854)	$ 4,940	$ 14,677
BI Development II, LLC
Schedule Of Equity Method Investments [Line Items]
Equity in earnings (losses) of unconsolidated affiliates	$ (14,854)	$ 4,940	$ 14,677

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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