Assets and Liabilities Held for Sale Asset and Liabilities Held for Sale Operations (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Assets and Liabilities Held for Sale Operations [Line Items]
PAC Business Annual Sales			$ 370
PAC Business pre-tax income	$ 5	$ 4

[Line Items] for Assets and Liabilities Held for Sale Operations [Table]

No definition available.

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Period Type:	duration