The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and Intangibles - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Goodwill, impairment loss	$ 0
Intangible assets (excluding goodwill), impairment loss	0
Amortization of intangible assets	32,000,000.0	$ 30,800,000	$ 30,700,000
Estimated amortization expense 2020	32,000,000.0
Estimated amortization expense 2021	32,000,000
Estimated amortization expense 2022	32,000,000
Estimated amortization expense 2023	31,700,000
Estimated amortization expense 2024	$ 31,700,000
Platte Valley [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset, useful life	38 years
Wattenberg Processing Plant [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset, useful life	38 years
Chipeta [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset, useful life	10 years
Delaware Basin Midstream LLC [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset, useful life	30 years