Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
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Business Combination, Acres Acquired

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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-SubTopic 30
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- Definition

The average floor rate on a group of price risk derivatives such as floors or collars. A payment or receipt is triggered if the market rate falls below the floor rate on the contract.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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The cash inflow from the additional capital contribution to the entity.

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-Name Accounting Standards Codification
-Glossary Financing Activities
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Per share or per unit amount of equity securities issued.

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Number of new stock issued during the period.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent Events (Details) $ / shares in Units, a in Thousands			2 Months Ended	9 Months Ended
	Oct. 21, 2016 USD ($) $ / shares shares	Oct. 17, 2016 a	Dec. 01, 2016 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Oct. 31, 2016 MMBTU	Oct. 31, 2016 MBbls	Oct. 31, 2016 $ / bbl	Oct. 31, 2016 $ / MMBTU	Oct. 14, 2016 USD ($)	Feb. 23, 2016 USD ($)	Feb. 22, 2016 USD ($)	Feb. 02, 2016 $ / shares
Subsequent Event [Line Items]
Shares issued, price per share (in usd per share) \| $ / shares													$ 4.685
Net proceeds from offering				$ 182,791,000	$ 462,833,000
Revolving Credit Facility [Member] \| Line of Credit [Member]
Subsequent Event [Line Items]
Line of credit facility, current borrowing capacity											$ 1,150,000,000.0	$ 1,525,000,000.0
Subsequent Event [Member] \| Public Offering [Member]
Subsequent Event [Line Items]
Issuance of common stock (in shares) \| shares	55,200,000
Shares issued, price per share (in usd per share) \| $ / shares	$ 10.80
Net proceeds from offering	$ 584,000,000
Subsequent Event [Member] \| Over-Allotment Option [Member]
Subsequent Event [Line Items]
Issuance of common stock (in shares) \| shares	7,200,000
Subsequent Event [Member] \| Williston Basin Acquisition [Member]
Subsequent Event [Line Items]
Acres acquired \| a		55
Subsequent Event [Member] \| Revolving Credit Facility [Member] \| Line of Credit [Member]
Subsequent Event [Line Items]
Line of credit facility, current borrowing capacity										$ 1,150,000,000.0
Subsequent Event [Member] \| Commodity derivative instruments [Member] \| Commodity Contract Maturing in 2017 [Member]
Subsequent Event [Line Items]
Total notional amount						668,000	2,338
Subsequent Event [Member] \| Commodity derivative instruments [Member] \| Commodity Contract Maturing in 2018 [Member]
Subsequent Event [Line Items]
Total notional amount						62,000	1,219
Subsequent Event [Member] \| Commodity derivative instruments [Member] \| Commodity Contract Maturing in 2019 [Member]
Subsequent Event [Line Items]
Total notional amount \| MBbls							93
Subsequent Event [Member] \| Crude oil [Member] \| Commodity derivative instruments [Member]
Subsequent Event [Line Items]
Weighted average floor price (in dollars per barrel) \| $ / bbl								51.73
Subsequent Event [Member] \| Natural Gas [Member] \| Commodity derivative instruments [Member]
Subsequent Event [Line Items]
Weighted average floor price (in dollars per barrel) \| $ / MMBTU									3.38
Scenario, Forecast [Member] \| Williston Basin Acquisition [Member]
Subsequent Event [Line Items]
Consideration to be paid for Purchase Agreement			$ 785,000,000