CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Current Assets
Cash and cash equivalents	$ 443.8	$ 376.1
Accounts receivable, net	155.7	278.2
Income tax receivable	18.6	87.3
Fair value of derivative contracts	0.0	146.8
Oil, gas and NGL inventories, at lower of average cost or market	10.4	13.3
Prepaid expenses and other	11.6	30.1
Total Current Assets	640.1	931.8
Property, Plant and Equipment (successful efforts method for gas and oil properties)
Proved properties	14,232.5	13,314.9
Unproved properties	871.5	691.0
Marketing and other	301.8	297.9
Materials and supplies	32.7	38.5
Total Property, Plant and Equipment	15,438.5	14,342.3
Less Accumulated Depreciation, Depletion and Amortization
Exploration and production	8,797.7	6,870.2
Marketing and other	101.8	87.5
Total Accumulated Depreciation, Depletion and Amortization	8,899.5	6,957.7
Net Property, Plant and Equipment	6,539.0	7,384.6
Fair value of derivative contracts	0.0	23.2
Other noncurrent assets	66.3	58.6
TOTAL ASSETS	7,245.4	8,398.2
Current Liabilities
Checks outstanding in excess of cash balances	12.3	29.8
Accounts payable and accrued expenses	269.7	351.7
Production and property taxes	30.1	46.1
Interest payable	32.9	36.4
Fair value of derivative contracts	169.8	0.8
Current portion of long-term debt	0.0	176.8
Total Current Liabilities	514.8	641.6
Long-term debt	2,020.9	2,014.7
Deferred income taxes	825.9	1,479.8
Asset retirement obligations	225.8	204.9
Fair value of derivative contracts	32.0	4.0
Other long-term liabilities	123.3	105.3
Commitments and Contingencies (Note 10)
EQUITY
Common stock – par value $0.01 per share; 500.0 million shares authorized; 240.7 million and 177.3 million shares issued, respectively	2.4	1.8
Treasury stock – 1.1 million and 0.5 million shares, respectively	(22.9)	(14.6)
Additional paid-in capital	1,366.6	554.8
Retained earnings	2,173.3	3,418.3
Accumulated other comprehensive (loss) income	(16.7)	(12.4)
Total Common Shareholders' Equity	3,502.7	3,947.9
TOTAL LIABILITIES AND EQUITY	$ 7,245.4	$ 8,398.2

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.