CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
REVENUES
Oil sales	$ 221.7	$ 143.8
Gas sales	134.5	85.1
NGL sales	29.0	13.6
Other revenue	4.0	2.3
Purchased oil and gas sales	30.9	16.5
Total Revenues	420.1	261.3
OPERATING EXPENSES
Purchased oil and gas expense	29.4	16.9
Lease operating expense	69.2	60.0
Transportation and processing costs	70.2	73.6
Gathering and other expense	1.5	1.3
General and administrative	33.6	48.5
Production and property taxes	29.1	17.8
Depreciation, depletion and amortization	191.8	240.0
Exploration expenses	0.4	0.3
Impairment	0.1	1,182.4
Total operating expenses	425.3	1,640.8
Net gain (loss) from asset sales	0.0	0.5
OPERATING INCOME (LOSS)	(5.2)	(1,379.0)
Realized and unrealized gains (losses) on derivative contracts (Note 7)	160.9	50.9
Interest and other income (expense)	0.6	2.1
Interest expense	(33.8)	(36.7)
INCOME (LOSS) BEFORE INCOME TAXES	122.5	(1,362.7)
Income tax (provision) benefit	(45.6)	498.9
NET INCOME (LOSS)	$ 76.9	$ (863.8)
Earnings per common share
Earnings Per Share, Basic	$ 0.32	$ (4.55)
Earnings Per Share, Diluted	$ 0.32	$ (4.55)
Weighted-average common shares outstanding
Used in basic calculation (in shares)	240.2	189.7
Used in diluted calculation (in shares)	240.3	189.7
Dividends per common share (in dollars per share)	$ 0.00	$ 0.00