Derivative Instruments - Notional Amounts of Derivative Instruments (Details) $ in Thousands, Mcf in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2020 Mcf	Jun. 30, 2020 USD ($) Mcf	Dec. 31, 2019 USD ($)
Commodity Member
Derivative [Line Items]
Notional amount	1,460.6	1,248.5
Basis Swap
Derivative [Line Items]
Notional amount	1,290.4	1,179.4
Interest Rate Swap
Derivative [Line Items]
Derivative notional amount | $		$ 581,218	$ 160,000
Commodity Swap Purchased
Derivative [Line Items]
Notional amount		21.9
Basis Swap Purchased
Derivative [Line Items]
Notional amount		12.7