Selected Balance Sheet Data

3 Months Ended

Mar. 31, 2015

Balance Sheet Related Disclosures [Abstract]

Selected Balance Sheet Data

Selected Balance Sheet Data

(Thousands of Dollars)	March 31, 2015			Dec. 31, 2014
Accounts receivable, net
Accounts receivable	$	338,093		$	346,007
Less allowance for bad debts	(22,626		)	(23,122		)
	$	315,467		$	322,885

(Thousands of Dollars)	March 31, 2015		Dec. 31, 2014
Inventories
Materials and supplies	$	56,703	$	55,491
Fuel	78,109		80,963
Natural gas	60,529		102,525
	$	195,341	$	238,979

(Thousands of Dollars)	March 31, 2015			Dec. 31, 2014
Property, plant and equipment, net
Electric plant	$	10,987,784		$	10,927,867
Natural gas plant	3,248,795			3,210,242
Common and other property	828,284			827,708
Plant to be retired (a)	64,130			71,534
Construction work in progress	873,437			828,620
Total property, plant and equipment	16,002,430			15,865,971
Less accumulated depreciation	(4,306,554		)	(4,239,015		)
	$	11,695,876		$	11,626,956

^(a)  PSCo has received approval for early retirement of Cherokee Unit 3 and Valmont Unit 5 between 2015 and 2017. Amounts are presented net of accumulated depreciation.