CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows provided by (used in) operating activities:
Net income	$ 157,608	$ 155,717	$ 123,181
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	1,403,175	893,719	476,391
Stock based compensation expense	14,209	14,473	9,368
Pension/OPEB costs	23,897	40,050	34,196
Loss on extinguishment of debt, net	0	0	45,939
Other non-cash adjustments	(28,036)	10,072	2,080
Deferred income taxes	87,411	85,432	61,217
Change in accounts receivable	(72,600)	(33,146)	21,906
Change in accounts payable and other liabilities	(84,689)	106,433	13,297
Change in prepaid expenses, income taxes and other current assets	71,706	(50,570)	(44,855)
Net cash provided by operating activities	1,572,681	1,222,180	742,720
Cash flows provided from (used by) investing activities:
Capital expenditures - Business operations	(748,361)	(480,888)	(230,966)
Capital expenditures - Integration activities	(76,478)	(96,991)	(24,999)
Cash transferred from (to) escrow	43,012	(115,000)	0
Cash paid for the Acquired Business (net of cash acquired)	0	(82,560)	0
Other assets purchased and distributions received, net	19,155	1,484	673
Net cash used by investing activities	(762,672)	(773,955)	(255,292)
Cash flows provided from (used by) financing activities:
Long-term debt borrowings	575,000	0	1,117,476
Financing costs paid	(5,444)	(12,868)	(2,204)
Long-term debt payments	(552,394)	(7,236)	(1,027,408)
Premium paid to retire debt	0	0	(66,868)
Issuance of common stock	0	0	751
Dividends paid	(746,387)	(529,389)	(312,366)
Repayment of customer advances for construction, distributions to noncontrolling interests and other	(5,953)	(6,162)	(1,743)
Net cash used by financing activities	(735,178)	(555,655)	(292,362)
Increase (decrease) in cash and cash equivalents	74,831	(107,430)	195,066
Cash and cash equivalents at January 1,	251,263	358,693	163,627
Cash and cash equivalents at December 31,	326,094	251,263	358,693
Cash paid during the period for:
Interest	653,500	511,354	364,167
Income taxes (refunds)	(19,424)	19,885	59,735
Non-cash investing and financing activities:
Financing obligation for contribution of real property to pension plan	58,100	0	0
Reduction of pension obligation	(58,100)	0	0
Shares issued for the Acquired Business	0	5,217,899	0
Assumed debt	0	3,456,782	0
Other acquired liabilities	0	987,510	0
Capital expenditures made with accounts payable	$ 1,338	$ (43,978)	$ 0