Fair Value Measurements - Impairment of Assets Measured on a Non-Recurring Basis (Details) - Fair Value, Measurements, Nonrecurring - Level 3 - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Impairment Charges	$ 6,830	$ 66,532
Equity Method Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair Value Measurements	8,175	37,396
Impairment Charges	6,830	47,112
Land, buildings and improvements and intangibles
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair Value Measurements	0	12,148
Impairment Charges	$ 0	$ 19,420