Supplemental Disclosures to the Consolidated Statements of Cash Flows (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Non-cash issuance of common stock	$ 68	$ 105
Stock-based compensation expense, equity awards	49	60
Prior Fiscal Periods Acquisitions [Member]
Deferred purchase consideration from prior years' acquisitions	30	$ 10
Putnam [Member]
Reduction of net cash flow for operations by discontinued operations	$ 82