Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2012

Defined Benefit Plan Disclosure [Line Items]

Components of net periodic benefit cost

	Defined Benefit Pension Plans
(in $ millions)	Year Ended December  31, 2012			Year Ended December  31, 2011			Year Ended December  31, 2010
Interest cost		25			27			27
Expected return on plan assets		(31	)		(31	)		(28	)
Recognized net actuarial loss		13			5			2
Net periodic benefit cost		7			1			1

	Post-Retirement Benefit Plans
(in $ millions)	Year Ended December  31, 2012			Year Ended December  31, 2011			Year Ended December  31, 2010
Interest cost		—			1			1
Amortization of prior service cost		—			(4	)		(6	)
Recognized net actuarial gain		(4	)		(1	)		(1	)
Net periodic benefit gain		(4	)		(4	)		(6	)

Weighted average assumptions to measure the benefit obligation

	December 31, 2012			December 31, 2011
Defined Benefit Pension Plans
Discount rate		3.6	%		4.2	%
Expected long-term return on plan assets		7.2	%		7.2	%
Post-Retirement Benefit Plans
Discount rate		3.8	%		4.1	%

Fair values of the Company's pension plan assets

	Pension Plan Assets
($ in millions)	Level 1		Level 2		Total
Common & commingled trust funds		—		438		438
Mutual funds		47		—		47
Money market funds		—		12		12
Total		47		450		497

The fair values of the Company’s pension plan assets by asset category as of December 31, 2011 are as follows:

	Pension Plan Assets
($ in millions)	Level 1		Level 2		Total
Common & commingled trust funds		—		399		399
Mutual funds		31		—		31
Money market funds		—		10		10
Total		31		409		440

Future Benefit Payments of defined benefit pension and other post-retirement benefit plans

(in $ millions)	Defined Benefit Pension Plans		Post-Retirement Benefit Plans
2013		28		1
2014		30		1
2015		32		1
2016		35		—
2017		37		—
Five years thereafter		275		1
		437		4

Defined Benefit Pension Plans [Member]

Defined Benefit Plan Disclosure [Line Items]

Summary of changes in the benefit obligation and fair value of assets

	Defined Benefit Pension Plans
(in $ millions)	Year Ended December  31, 2012			Year Ended December  31, 2011
Benefit obligation, beginning of year		614			516
Interest cost		25			27
Actuarial loss		44			94
Benefits paid		(24	)		(23	)
Currency translation adjustment and other		4			—
Benefit obligation, end of year		663			614
Fair value of plan assets, beginning of year		440			424
Return on plan assets		51			23
Employer contribution		26			16
Benefits paid		(24	)		(23	)
Currency translation adjustment and other		4			—
Fair value of plan assets, end of year		497			440
Funded status		(166	)		(174	)

Post-Retirement Benefit Plans [Member]

Defined Benefit Plan Disclosure [Line Items]

Summary of changes in the benefit obligation and fair value of assets

	Post-Retirement Benefit Plans
(in $ millions)	Year Ended December  31, 2012			Year Ended December  31, 2011
Benefit obligation, beginning of year		9			12
Interest cost		—			1
Actuarial gains		—			(3	)
Benefits paid		(1	)		(1	)
Benefit obligation, end of year		8			9
Fair value of plan assets, beginning of year		—			—
Employer contribution		1			1
Benefits paid		(1	)		(1	)
Fair value of plan assets, end of year		—			—
Funded status		(8	)		(9	)