STATEMENTS OF CONSOLIDATED CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net income	$ 479,769	$ 227,700	$ 156,929
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred income taxes	234,019	153,912	234,776
Depreciation, depletion and amortization	339,297	270,285	196,078
Gain on dispositions	(202,928)
Provision for (recoveries of) losses on accounts receivable	1,581	5,134	(1,263)
Other income	(34,138)	(12,898)	(8,585)
Stock based compensation expense	20,080	14,104	6,768
Reimbursements for tenant improvements		4,053	12,212
Changes in other assets and liabilities:
Accounts receivable and unbilled revenues	14,317	(6,330)	66,327
Inventory	1,117	45,104	73,181
Prepaid expenses and other	22,812	126,042	11,836
Accounts payable	42,262	(36,853)	(107,745)
Derivative instruments, at fair value	(4,775)	(7,609)	56,510
Other current liabilities	(15,054)	(2,963)	33,502
Other items, net	16,905	10,059	(4,785)
Net cash provided by operating activities	915,264	789,740	725,741
Cash flows from investing activities:
Capital expenditures	(1,274,280)	(1,246,932)	(963,908)
Capital contributions to Nora Gathering LLC			(6,400)
Tenant improvements		(4,053)	(12,212)
Proceeds from sale of available-for-sale securities	29,947	12,306
Proceeds from sale of assets	619,999
Investment in available-for-sale securities		(750)	(3,000)
Net cash used in investing activities	(624,334)	(1,239,429)	(985,520)
Cash flows from financing activities:
Dividends paid	(131,625)	(127,292)	(115,368)
Proceeds from issuance of common stock		537,206
Proceeds from issuance of long-term debt	750,000		700,000
Debt issuance costs and revolving credit facility origination fee	(11,738)	(10,962)	(6,874)
(Decrease) increase in short-term loans	(53,650)	48,650	(314,917)
Repayments and retirements of long-term debt	(15,457)		(4,300)
Proceeds and tax benefits from exercises under employee compensation plans	2,791	2,087	1,238
Net cash provided by financing activities	540,321	449,689	259,779
Net change in cash and cash equivalents	831,251
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	831,251	0	0
Cash paid (received) during the year for:
Interest, net of amount capitalized	130,719	127,904	107,475
Income taxes, net	$ 47,242	$ (129,495)	$ (120,074)

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).