Selected Balance Sheet Data

12 Months Ended

Dec. 31, 2015

Balance Sheet Related Disclosures [Abstract]

Selected Balance Sheet Data

Selected Balance Sheet Data

(Thousands of Dollars)	Dec. 31, 2015			Dec. 31, 2014
Accounts receivable, net
Accounts receivable	$	776,494		$	884,225
Less allowance for bad debts	(51,888		)	(57,719		)
	$	724,606		$	826,506

(Thousands of Dollars)	Dec. 31, 2015		Dec. 31, 2014
Inventories
Materials and supplies	$	290,690	$	244,099
Fuel	202,271		183,249
Natural gas	115,623		169,835
	$	608,584	$	597,183

(Thousands of Dollars)	Dec. 31, 2015			Dec. 31, 2014
Property, plant and equipment, net
Electric plant	$	36,464,050		$	33,203,139
Natural gas plant	4,944,757			4,643,452
Common and other property	1,709,508			1,611,486
Plant to be retired (a)	38,249			71,534
CWIP	1,256,949			2,005,531
Total property, plant and equipment	44,413,513			41,535,142
Less accumulated depreciation	(13,591,259		)	(13,168,418		)
Nuclear fuel	2,447,251			2,347,422
Less accumulated amortization	(2,063,654		)	(1,957,230		)
	$	31,205,851		$	28,756,916

^(a)  PSCo’s Cherokee Unit 3 was retired in August 2015. In 2017, PSCo expects to both early retire Valmont Unit 5 and convert Cherokee Unit 4 from a coal-fueled generating facility to natural gas, as approved by the CPUC. Amounts are presented net of accumulated depreciation.