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Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Land Brokerage Services \| Brigham Land Management
Related Party Transaction [Line Items]
Related party transaction, amount		$ 0.1	$ 0.1	$ 0.6
Leasing of Acreage Arrangement \| Ben M. Brigham
Related Party Transaction [Line Items]
Amount received from related party		$ 0.4	0.0	$ 0.6
Borrowings From Related Party \| Brigham Operating
Related Party Transaction [Line Items]
Related party transaction, amount			$ 7.0
Related party transaction, interest rate (as a percent)	7.00%