Consolidated Statement of Equity - Shares of Common Stock - shares shares in Millions	Total	Common Stock
Beginning balance at Dec. 31, 2017		734
Number of common shares issued - stock compensation		0
Ending balance at Mar. 31, 2018		734
Number of common shares issued - stock compensation		1
Ending balance at Jun. 30, 2018		735
Beginning balance at Dec. 31, 2018	975	975
Number of common shares issued - stock compensation		1
Ending balance at Mar. 31, 2019		976
Number of common shares issued - stock compensation		2
Ending balance at Jun. 30, 2019	978	978