CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Operating Activities:
Net income	$ 62,707	$ 77,568
Non-cash items included in net income:
Depreciation and amortization	93,293	84,273
Provision for deferred income taxes	18,380	30,783
Power and natural gas cost amortizations, net	10,418	9,470
Amortization of debt expense and premium	2,876	3,186
Equity-related AFUDC	(2,875)	(1,655)
Other	52,859	32,958
Contributions to defined benefit pension plan	(44,000)	(26,000)
Changes in working capital components:
Accounts and notes receivable	61,106	76,285
Materials and supplies, fuel stock and natural gas stored	941	(16,260)
Other current assets	7,209	(28,167)
Accounts payable	(10,783)	(11,994)
Other current liabilities	5,277	9,977
Net cash provided by operating activities	257,408	240,424
Investing Activities:
Utility property capital expenditures (excluding equity-related AFUDC)	(178,440)	(169,598)
Other capital expenditures	(3,908)	(2,730)
Federal grant payments received	5,902	13,398
Cash paid by subsidiaries for acquisitions, net of cash received	(50,310)	(199)
Decrease (increase) in funds held for clients	(9,599)	43,321
Purchase of securities available for sale	(88,843)	(47,299)
Sale and maturity of securities available for sale	103,545
Other	(7,412)	(4,604)
Net cash used in investing activities	(229,065)	(167,711)
Financing Activities:
Net increase (decrease) in short-term borrowings	21,000	(13,500)
Borrowings from Ecova line of credit	28,000
Repayment of borrowings from Ecova line of credit	(5,000)
Redemption and maturity of long-term debt	(11,363)	(204)
Maturity of nonrecourse long-term debt of Spokane Energy	(10,153)	(9,258)
Long-term debt and short-term borrowing issuance costs	(177)	(2,362)
Cash paid for settlement of interest rate swap agreements	(18,547)	(10,557)
Issuance of common stock	28,699	21,216
Cash dividends paid	(51,215)	(47,685)
Purchase of subsidiary noncontrolling interest	(917)	(6,179)
Increase (decrease) in client fund obligations	(5,220)	3,978
Issuance of subsidiary noncontrolling interests	3,714
Other	1,126	528
Net cash used in financing activities	(20,053)	(64,023)
Net increase in cash and cash equivalents	8,290	8,690
Cash and cash equivalents at beginning of period	74,662	69,413
Cash and cash equivalents at end of period	82,952	78,103
Cash paid during the period:
Interest	43,487	41,582
Income taxes	12,527	24,506
Non-cash financing and investing activities:
Accounts payable for capital expenditures	3,556	2,642
Redeemable noncontrolling interests	$ (8,274)	$ 5,147