Condensed Consolidated Statements Of Cash Flows (USD $) In Millions	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
OPERATING ACTIVITIES
Net income	$ 167.3	$ 191.4
Discontinued operations, net of income tax		(43.2)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	377.4	299.0
Deferred income taxes	95.7	117.2
Abandonment and impairment	10.7	16.9
Share-based compensation	10.8	7.1
Amortization of debt issuance costs and discounts	1.5	0.6
Dry exploratory well expense	0.5
Net gain from asset sales	(0.2)	(1.4)
Income from unconsolidated affiliates	(2.2)	(1.4)
Distributions from unconsolidated affiliates and other	2.6	1.2
Unrealized gain on basis-only swaps	(58.8)	(62.1)
Changes in operating assets and liabilities	23.3	(57.2)
Net Cash Provided by Operating Activities of Continuing Operations	628.6	468.1
INVESTING ACTIVITIES
Property acquisitions	(29.8)	(63.8)
Property, plant and equipment, including dry exploratory well expense	(632.0)	(592.3)
Proceeds from disposition of assets	1.6	4.7
Change in notes receivable		52.9
Net Cash Used in Investing Activities of Continuing Operations	(660.2)	(598.5)
FINANCING ACTIVITIES
Checks outstanding in excess of cash balances	(1.5)	14.6
Long-term debt issued	200.0
Long-term debt issuance costs paid		(9.8)
Current portion long-term debt repaid	(58.5)
Repayments of notes payable		(39.3)
Long-term debt repaid	(100.0)	(102.0)
Other capital contributions	1.0
Equity contribution		250.0
Dividends paid	(7.1)
Distribution from Questar	0.2
Distribution to noncontrolling interest	(2.5)	(2.4)
Net Cash Provided from Financing Activities of Continuing Operations	31.6	111.1
CASH USED IN CONTINUING OPERATIONS		(19.3)
Cash provided by operating activities of discontinued operations		68.6
Cash used in investing activities of discontinued operations		(39.9)
Cash used in financing activities of discontinued operations		(26.9)
Effect of change in cash and cash equivalents of discontinued operations		(1.8)
Change in cash and cash equivalents		(19.3)
Beginning cash and cash equivalents		19.3
Ending cash and cash equivalents