Acquisitions - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended	2 Months Ended	3 Months Ended
	Jan. 27, 2025	Jan. 17, 2025	Jan. 31, 2025	Mar. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Franklin Mountain Energy
Consideration:
Coterra common stock issued in exchange for FME equity interests (in shares)	28,190,682		28,190,682
Coterra common stock closing price on January 27, 2025 (in dollar per share)	$ 27.83
Total value of Coterra common stock issued	$ 785		$ 785
Cash consideration			1,700	$ 1,735
Total consideration	2,520		$ 2,500
Assets acquired:
Current assets	160
Proved oil and gas properties	1,842
Unproved oil and gas properties	583
Gathering and pipeline systems	172
Other assets	6
Total assets acquired	2,763
Liabilities assumed:
Current liabilities	221
Asset retirement obligation	13
Other liabilities	9
Total liabilities assumed	243
Net assets acquired	$ 2,520
Restricted cash						$ 107
Consideration transferred, cash					$ 18
Avant
Consideration:
Cash consideration		$ 1,513
Total consideration		1,513
Assets acquired:
Current assets		44
Proved oil and gas properties		668
Unproved oil and gas properties		670
Gathering and pipeline systems		161
Other assets		1
Total assets acquired		1,544
Liabilities assumed:
Current liabilities		20
Asset retirement obligation		6
Other liabilities		5
Total liabilities assumed		31
Net assets acquired		$ 1,513
Restricted cash						$ 98
Consideration transferred, cash					$ 11