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Period Type:	duration

Equity and Noncontrolling Interests Equity and Noncontrolling Interests - Additional Information (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2013
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount	$ 3,650
Authorization in November 2013
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount		$ 3,000