Contingencies, Commitments and Guarantees (details) (USD $)	0 Months Ended	6 Months Ended	7 Months Ended
	Jun. 26, 2013	Jun. 30, 2013	Apr. 30, 2002 item	Mar. 08, 2013 item	Feb. 07, 2013 item	Dec. 31, 2012	Mar. 27, 2012 item	Jul. 26, 2011	Oct. 25, 2010 item	Mar. 22, 2010 item
Contingencies and Commitments disclosure
Number of purported class action suits filed against TPC and other insurers in state court in West Virginia relative to asbestos direct action litigation			2
Maximum lump-sum payment included in the settlement reached in November 2003 relative to Statutory and Hawaii Actions		$ 412,000,000
Maximum payment required under May 2004 settlement resolving substantially all pending and similar future Common Law Claims relative to Statutory and Hawaii Actions		90,000,000
Number of remaining objectors to which the notice of the 1986 Orders were deemed insufficient to bar contribution claims against TPC										1
Number of other reinsurers beside American Re against which judgment was entered in a reinsurance dispute									3
Judgment amount awarded to Company in reinsurance dispute		251,000,000							251,000,000
Interest amount awarded to Company in reinsurance dispute		231,000,000							169,000,000
Number of discrete issues modified in part by the summary judgment in reinsurance dispute					2
Number of issues on which reinsurers filed motions to reargue in reinsurance dispute				1
Total judgment amount awarded to Company in reinsurance dispute		482,000,000							420,000,000
Interest rate accruing on judgment against non-settling defendants		9.00%
Preliminary class settlement amount approved by court in workers' compensation matter, amount payable by defendants								450,000,000
Number of parties who objected to the settlement and filed notices of appeal in workers' compensation matter							3
Payment received from settlement fund in workers' compensation matter	91,000,000
Percentage of Company's allocated settlement received in workers' compensation matter	98.00%
Approximate amount anticipated for receipt from settlement fund in workers' compensation matter	2,000,000
Percentage of Company's allocated settlement still to be paid in workers' compensation matter	2.00%
Unfunded commitments to private equity limited partnerships and real estate partnerships		$ 1,400,000,000				$ 1,270,000,000