CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net income	$ 611	$ 472	$ 496
Other comprehensive income (loss):
Fair market value adjustment on cash flow hedges, net of income taxes of $8 million, $34 million and $12 million	(12)	(51)	(18)
Reclassification adjustment for net realized losses on cash flow hedges included in interest expense, net of income taxes of $17 million, $21 million and $23 million	26	31	34
Foreign currency translation	4	(8)	3
Total other comprehensive income (loss)	18	(28)	19
Comprehensive income	$ 629	$ 444	$ 515