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Supplemental Disclosures to the Consolidated Statements of Cash Flows (Narrative) (Details) - USD ($) $ in Millions | 9 Months Ended
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Sep. 30, 2017 | Sep. 30, 2016
Supplemental Disclosure to the Consolidate Statements of Cash Flows [Line Items] |  |
Deferred and contingent consideration from prior years acquisition | $ 127 | $ 96
Contingent consideration from prior year's acquisitions | 80 | 43
Net charge for adjustments related to acquisition related accounts | (3) | 5
Payment of contingent consideration | 27 | 42
Non-cash issuance of common stock | 88 | 71
Stock-based compensation expense, equity awards | 111 | 84
Effective income tax rate reconciliation, share-based compensation, excess tax benefit, amount | (58) |
Adjustments to additional paid in capital, income tax benefit from share-based compensation |  | 30
Prior Fiscal Periods Acquisitions |  |
Supplemental Disclosure to the Consolidate Statements of Cash Flows [Line Items] |  |
Deferred purchase consideration from prior years' acquisitions | 47 | 53
Contingent consideration from prior year's acquisitions | $ 107 | $ 85

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- Definition Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 740 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=79981250&loc=d3e23524-113945 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644 + Details
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