Stockholder's Equity (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Mar. 31, 2011 Predecessor	Dec. 31, 2010 Predecessor
Stockholder's Equity (Deficit)
Common stock, shares issued			1
Common stock, shares outstanding		1	1
Tax benefit associated with deduction for pension funding recognized in equity contribution	$ 100		$ 100
Amount recorded in equity for excess tax deduction					56
Dividends
Non-cash dividend to QSC		28
Cash dividend declared to QSC		600	840	1,000	2,300
Cash dividend paid to QSC		$ 900	$ 1,150	$ 530	$ 2,260