Equity Investees (Consolidated Financial Statements Related to Equity Investees) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Equity Method Investments and Joint Ventures [Abstract]
Genesis’ share of operating earnings	$ 18,094	$ 16,490	$ 42,627	$ 34,522
Amortization of excess purchase price	(3,872)	(3,872)	(7,745)	(7,745)
Net equity in earnings	14,222	12,618	34,882	26,777
Distributions received (1)	$ 21,914	$ 18,394	$ 51,430	$ 38,959

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

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