Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2014

Commitments and Contingencies Disclosure [Abstract]

Schedule of Long-term Contracts for Purchase of Electric Power

The Company's expenses under these PUD contracts were as follows for the years ended December 31:

(Dollars in Thousands)	2014		2013		2012
PUD contract costs	$	69,661	$	63,365	$	70,188

As of December 31, 2014, the Company purchased portions of the power output of the PUDs' projects as set forth in the following table:

		Company's Current Share of
(Dollars in Thousands)	Contract Expiration	Percent of Output		Megawatt Capacity	Estimated 2015 Costs		2015 Debt Service Costs		Interest included in 2015 Debt Service Costs		Debt Outstanding
Chelan County PUD:
Rock Island Project	2031	25.0	%	156	$	29,854	$	11,009	$	6,174	$	98,191
Rocky Reach Project	2031	25.0	%	325	27,583		8,245		3,343		53,299
Douglas County PUD:
Wells Project	2018	29.9	%	251	17,277		9,383		2,597		64,931
Grant County PUD:
Priest Rapids Development	2052	0.6	%	8	3,689		2,087		1,245		19,828
Wanapum Development	2052	0.6	%	9	3,689		2,087		1,245		19,828
Total				749	$	82,092	$	32,811	$	14,604	$	256,077

Schedule of Long-term Purchase Commitments

These contracts have varying terms and may include escalation and termination provisions.

(Dollars in Thousands)	2015		2016		2017		2018		2019		Thereafter		Total
Columbia River projects	$	73,023	$	75,360	$	74,851	$	65,981	$	53,837	$	644,666	$	987,718
Other utilities	16,136		18,884		11,823		1,257		890		—		48,990
Non-utility contracts	117,372		153,863		199,056		204,292		209,699		1,354,191		2,238,473
Total	$	206,531	$	248,107	$	285,730	$	271,530	$	264,426	$	1,998,857	$	3,275,181

The quantified obligations are based on the FERC and NEB (National Energy Board) currently authorized rates, which are subject to change. 

Demand Charge Obligations (Dollars in Thousands)	2015		2016		2017		2018		2019		Thereafter		Total
Firm transportation service	$	154,121	$	147,424	$	144,751	$	131,484	$	112,249	$	373,958	$	1,063,987
Firm storage service	6,528		5,337		5,209		1,407		1,535		1,258		21,274
Total	$	160,649	$	152,761	$	149,960	$	132,891	$	113,784	$	375,216	$	1,085,261

The following table summarizes the Company’s estimated obligations for service contracts through the terms of its existing contracts.

Service Contract Obligations (Dollars in Thousands)	2015		2016		2017		2018		2019		Thereafter		Total
Energy production service contracts	$	32,979	$	15,650	$	5,558	$	4,064	$	2,372	$	23,443	$	84,066
Automated meter reading system	25,402		16,081		13,362		13,996		14,602		51,986		135,429
Total	$	58,381	$	31,731	$	18,920	$	18,060	$	16,974	$	75,429	$	219,495