Selected Balance Sheet Data

3 Months Ended

Mar. 31, 2016

Balance Sheet Related Disclosures [Abstract]

Selected Balance Sheet Data

Selected Balance Sheet Data

(Thousands of Dollars)	March 31, 2016			Dec. 31, 2015
Accounts receivable, net
Accounts receivable	$	279,677		$	321,004
Less allowance for bad debts	(19,456		)	(20,122		)
	$	260,221		$	300,882

(Thousands of Dollars)	March 31, 2016		Dec. 31, 2015
Inventories
Materials and supplies	$	58,766	$	58,128
Fuel	71,506		78,586
Natural gas	35,125		68,848
	$	165,397	$	205,562

(Thousands of Dollars)	March 31, 2016			Dec. 31, 2015
Property, plant and equipment, net
Electric plant	$	11,888,887		$	11,856,126
Natural gas plant	3,490,099			3,420,249
Common and other property	863,165			862,840
Plant to be retired (a)	34,607			38,249
Construction work in progress	452,786			408,963
Total property, plant and equipment	16,729,544			16,586,427
Less accumulated depreciation	(4,459,591		)	(4,414,216		)
	$	12,269,953		$	12,172,211

^(a)  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 Colorado Public Utilities Commission (CPUC).  Amounts are presented net of accumulated depreciation.