Consolidated Statements of Equity - Shares of Common Stock - shares shares in Millions	Total	Common Stock
Beginning balance at Dec. 31, 2015		729
Shares issued - stock-based compensation		2
Ending balance at Dec. 31, 2016		731
Shares issued - stock-based compensation		3
Ending balance at Dec. 31, 2017	734	734
Shares issued - stock-based compensation		1
Shares issued - acquisitions		240
Ending balance at Dec. 31, 2018	975	975

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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