Jointly-Owned Facilities (Details) (ARIZONA PUBLIC SERVICE COMPANY, USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Palo Verde Units 1 and 3
Interests in jointly-owned facilities
Percent Owned	29.10%
Plant in Service	$ 1,701,844
Accumulated Depreciation	1,027,523
Construction Work in Progress	22,400
Palo Verde Unit 2
Interests in jointly-owned facilities
Percent Owned	16.80%
Plant in Service	543,972
Accumulated Depreciation	338,918
Construction Work in Progress	10,095
Palo Verde Common
Interests in jointly-owned facilities
Percent Owned	28.00%
Plant in Service	538,818
Accumulated Depreciation	219,801
Construction Work in Progress	81,599
Palo Verde Sale Leaseback
Interests in jointly-owned facilities
Plant in Service	351,050
Accumulated Depreciation	225,925
Four Corners Units 4, 5 and Common
Interests in jointly-owned facilities
Percent Owned	63.00%
Plant in Service	809,946
Accumulated Depreciation	608,194
Construction Work in Progress	14,434
Navajo Generating Station Units 1, 2 and 3
Interests in jointly-owned facilities
Percent Owned	14.00%
Plant in Service	270,448
Accumulated Depreciation	150,501
Construction Work in Progress	2,864
Cholla common facilities
Interests in jointly-owned facilities
Percent Owned	63.30%
Plant in Service	148,299
Accumulated Depreciation	47,851
Construction Work in Progress	7,159
ANPP 500kV System
Interests in jointly-owned facilities
Percent Owned	34.20%
Plant in Service	98,145
Accumulated Depreciation	32,350
Construction Work in Progress	1,095
Navajo Southern System
Interests in jointly-owned facilities
Percent Owned	22.20%
Plant in Service	58,702
Accumulated Depreciation	16,937
Construction Work in Progress	518
Palo Verde - Yuma 500kV System
Interests in jointly-owned facilities
Percent Owned	18.00%
Plant in Service	12,115
Accumulated Depreciation	4,656
Construction Work in Progress	11,786
Four Corners Switchyards
Interests in jointly-owned facilities
Percent Owned	48.10%
Plant in Service	33,460
Accumulated Depreciation	9,052
Construction Work in Progress	185
Phoenix - Mead System
Interests in jointly-owned facilities
Percent Owned	17.10%
Plant in Service	39,758
Accumulated Depreciation	12,140
Palo Verde - Estrella 500kV System
Interests in jointly-owned facilities
Percent Owned	50.00%
Plant in Service	89,571
Accumulated Depreciation	14,883
Construction Work in Progress	21
Morgan-Pinnacle Peak System
Interests in jointly-owned facilities
Percent Owned	64.50%
Plant in Service	130,132
Accumulated Depreciation	6,651
Construction Work in Progress	1,042
Round Valley System
Interests in jointly-owned facilities
Percent Owned	50.00%
Plant in Service	488
Accumulated Depreciation	268
Palo Verde - Morgan System
Interests in jointly-owned facilities
Percent Owned	90.00%
Construction Work in Progress	$ 36,601