Equity Investees (Consolidated Financial Statements Related to Equity Investees) (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Genesis’ share of operating earnings	$ 14,411,000	$ 15,200,000	$ 46,365,000	$ 50,986,000
Amortization of differences attributable to Genesis’ carrying value of equity investments	(3,566,000)	(3,566,000)	(10,698,000)	(10,698,000)
Equity in earnings of equity investees	10,845,000	11,634,000	35,667,000	40,288,000
Distributions received	$ 16,078,000	$ 18,488,000	$ 52,587,000	$ 58,829,000

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

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