Mandatorily Convertible Preferred Stock and Other Bankruptcy Settlement Obligations (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended	12 Months Ended				0 Months Ended		3 Months Ended	12 Months Ended
	Dec. 09, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Series A Convertible Preferred Stock [Member]	Feb. 19, 2014 Subsequent Event [Member]	Dec. 09, 2013 AA [Member]	Dec. 31, 2013 AA [Member]	Dec. 31, 2013 AA [Member]	Dec. 31, 2012 AA [Member]	Dec. 31, 2011 AA [Member]
Mandatorily Convertible Preferred Stock and Other Bankruptcy Settlement Obligations [Line Items]
AAG Series A Preferred Stock		$ 3,833	$ 3,833						$ 3,329	$ 3,329
Single-dip equity obligations		1,246	1,246						1,246	1,246
Labor-related deemed claim		849	849						849	849
Mandatorily convertible preferred stock and other bankruptcy settlement obligations		5,928	5,928	0					5,424	5,424	0
Preferred shares optionally convertible		10,000,000	10,000,000
Preferred stock, par or stated value per share		$ 0.01	$ 0.01			$ 25
Preferred stock dividends rate per annum			6.25%
Conversion discount for unsecured creditors receiving AAG Preferred Stock		3.50%	3.50%						3.50%	3.50%
Series A Convertible Preferred Stock, conversion price floor (in usd per share)	$ 10.875
Series A Convertible Preferred Stock, conversion price cap (in usd per share)	$ 33.8080
Series A Convertible Preferred Stock, shares converted							107,000,000
Optional conversion of AAG Series A Preferred Stock into shares of AAG Common Stock on December 17, 2013			9,993,882				95,000,000
Dividend rate for single-dip unsecured claims not settled in Preferred Stock		12.00%	12.00%
Labor-related deemed claim		1,733	1,733	0	0				1,733	1,733	0	0
Value of initial distribution of common stock	595
Payments for payroll taxes associated with equity distributions to employees	$ 300							$ 300