Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating Activities:
Net income	$ 56,068	$ 46,462
Non-cash items included in net income:
Depreciation and amortization	40,291	35,379
Provision for deferred income taxes	34,030	(82)
Power and natural gas cost amortizations (deferrals), net	5,379	8,196
Amortization of debt expense	876	895
Amortization of investment in exchange power	613	613
Stock-based compensation expense	2,313	1,707
Equity-related AFUDC	(2,261)	(2,215)
Pension and other postretirement benefit expense	9,475	9,217
Amortization of Spokane Energy contract	3,558	3,271
Other	(12,747)	(3,077)
Contributions to defined benefit pension plan	(4,000)	(4,000)
Changes in working capital components:
Accounts and notes receivable	18,364	2,664
Materials and supplies, fuel stock and natural gas stored	10,263	22,571
Increase (Decrease) in Deposit Assets	(42,871)	(18,516)
Increase (Decrease) in Income Taxes Receivable	11,210	43,331
Other current assets	(10,978)	471
Accounts payable	(30,804)	(30,545)
Increase (Decrease) in Income Taxes Payable	1,067	20,162
Other current liabilities	15,701	10,274
Net cash provided by operating activities	105,547	146,778
Investing Activities:
Utility property capital expenditures (excluding equity-related AFUDC)	(88,878)	(81,597)
Other capital expenditures	(119)	(412)
Other	(2,657)	1,834
Net cash used in investing activities	(91,654)	(80,175)
Financing Activities:
Net decrease in short-term borrowings	(15,000)	(40,000)
Redemption and maturity of long-term debt	(792)	(639)
Maturity of nonrecourse long-term debt of Spokane Energy	0	(1,431)
Issuance of common stock	27,150	371
Payments for Repurchase of Common Stock	0	(2,920)
Cash dividends paid	(21,545)	(20,717)
Other	(1,423)	(1,329)
Net cash used in financing activities	(11,610)	(66,665)
Net increase (decrease) in cash and cash equivalents	2,283	(62)
Cash and cash equivalents at beginning of period	10,484	22,143
Cash and cash equivalents at end of period	$ 12,767	$ 22,081