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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 03, 2018
Goodwill [Line Items]
Goodwill	$ 323,314,000	$ 796,359,000
Impairment	473,045,000	0	$ 0
Impairment of intangible assets	0	0	18,650,000
Amortization expense	6,552,000	6,552,000	6,931,000
Estimated annual amortization expense expected, 2021	6,552,000
Estimated annual amortization expense expected, 2022	6,552,000
Estimated annual amortization expense expected, 2023	6,552,000
Estimated annual amortization expense expected, 2024	6,552,000
Estimated annual amortization expense expected, 2025	6,552,000
Customer Relationships
Goodwill [Line Items]
Impairment of intangible assets	$ 0	$ 0	$ 18,650,000
Useful life, customer relationship intangible assets	17 years
Midstream Acquisition
Goodwill [Line Items]
Goodwill	$ 323,314,000			$ 796,359,000
Other intangible assets				$ 128,781,000