Equity Investees (Consolidated Financial Statements Related to Equity Investees) (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Equity Method Investments and Joint Ventures [Abstract]
Genesis’ share of operating earnings	$ 21,926,000	$ 15,896,000	$ 39,654,000	$ 31,954,000
Amortization of differences attributable to Genesis’ carrying value of equity investments	(3,566,000)	(3,566,000)	(7,132,000)	(7,132,000)
Equity in earnings of equity investees	18,360,000	12,330,000	32,522,000	24,822,000
Distributions received	$ 20,828,000	$ 17,925,000	$ 40,511,000	$ 36,509,000

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

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