CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Current Assets
Cash and cash equivalents	$ 445.6	$ 1,160.1
Accounts receivable, net	330.8	441.9
Income Taxes Receivable, Current	55.7	0.0
Fair value of derivative contracts	163.6	339.0
Gas, oil and NGL inventories at lower of average cost or market	10.4	13.7
Prepaid expenses and other	38.0	46.8
Total Current Assets	1,044.1	2,001.5
Property, Plant and Equipment (successful efforts method for gas and oil properties)
Proved properties	12,686.4	12,278.7
Unproved properties	814.1	825.2
Marketing and resources	298.1	293.8
Material and supplies	41.6	54.3
Total Property, Plant and Equipment	13,840.2	13,452.0
Less Accumulated Depreciation, Depletion and Amortization
Exploration and production	6,415.1	6,153.0
Marketing and other	77.7	67.8
Total Accumulated Depreciation, Depletion and Amortization	6,492.8	6,220.8
Net Property, Plant and Equipment	7,347.4	7,231.2
Fair value of derivative contracts	6.1	9.9
Other noncurrent assets	35.5	44.2
TOTAL ASSETS	8,433.1	9,286.8
Current Liabilities
Checks outstanding in excess of cash balances	7.4	54.7
Accounts payable and accrued expenses	463.3	575.4
Income taxes payable	0.0	532.1
Production and property taxes	59.3	61.7
Interest payable	36.4	36.4
Derivative Liability, Current	1.0	0.0
Deferred income taxes	36.9	84.5
Total Current Liabilities	604.3	1,344.8
Long-term debt	2,218.5	2,218.1
Deferred income taxes	1,381.4	1,362.7
Asset retirement obligations	184.9	193.8
Derivative Liability, Noncurrent	1.6	0.0
Other long-term liabilities	$ 94.7	$ 92.1
Commitments and contingencies (Note 11)
EQUITY
Common stock - par value $0.01 per share; 500.0 million shares authorized; 177.0 million and 176.2 million shares issued, respectively	$ 1.8	$ 1.8
Treasury stock - 0.4 million and 0.8 million shares, respectively	(11.5)	(25.4)
Additional paid-in capital	538.1	535.3
Retained earnings	3,442.8	3,587.9
Accumulated other comprehensive loss	(23.5)	(24.3)
Total Common Shareholders' Equity	3,947.7	4,075.3
TOTAL LIABILITIES AND EQUITY	$ 8,433.1	$ 9,286.8

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.