Contingencies, Commitments and Guarantees (details) - Gain Contingencies (USD $) In Millions, unless otherwise specified	0 Months Ended	35 Months Ended		0 Months Ended
	Oct. 25, 2010 United States Fidelity & Guaranty Company v. American Re-Insurance Company, et al. [Member] item	Sep. 30, 2013 United States Fidelity & Guaranty Company v. American Re-Insurance Company, et al. [Member]	Feb. 07, 2013 United States Fidelity & Guaranty Company v. American Re-Insurance Company, et al. [Member] item	Jun. 26, 2013 Safeco Insurance Company of America, et al v American International Group, Inc, et al [Member]	Mar. 27, 2012 Safeco Insurance Company of America, et al v American International Group, Inc, et al [Member] item	Jul. 26, 2011 Safeco Insurance Company of America, et al v American International Group, Inc, et al [Member]
Gain Contingencies
Number of other reinsurers beside American Re against which judgment was entered in a reinsurance dispute	3
Total settlement amount	$ 420	$ 487
Interest amount included in settlement award	169	236
Initial settement amount	251	251
Interest rate accruing on judgment not yet paid	9.00%	9.00%
Number of discrete issues modified in part by the summary judgment in reinsurance dispute			2
Number of parties who objected to the settlement and filed notices of appeal in workers' compensation matter					3
Preliminary class settlement amount approved by court in workers' compensation matter, amount payable by defendants						450
Payment received from settlement fund				91
Percentage of Company's allocated settlement received in workers' compensation matter				98.00%
Approximate amount anticipated for receipt from settlement				$ 2
Percentage of Company's allocated settlement still to be paid in workers' compensation matter				2.00%