Commitments and Contingencies Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2012

Commitments and Contingencies Disclosure [Abstract]

Contractual Obligation, Fiscal Year Maturity Schedule

Future Minimum Rental Payments

Year	(in millions)
2013	$	14
2014	8
2015	8
2016	8
2017	8
Thereafter	66
Total	$	112

Expected Maturity Schedule of Debt

Expected Withdrawal Date	AGUS		AGMH		AGM		Total
	(in millions)
2013	$	—	$	—	$	22	$	22
2014	—		—		10		10
2015	—		—		10		10
2016	—		—		6		6
2017	—		—		13		13
2018-2037	200		—		0		200
2038-2057	—		—		—		—
2058-2077	150		300		—		450
Thereafter	—		430		—		430
Total	$	350	$	730	$	61	$	1,141