CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME Unaudited (Parenthetical) $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($)
Statement Of Income And Comprehensive Income
Net tax deficiency reclassified from capital surplus to applicable income tax expense	$ 1

Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration