v3.19.3.a.u2
Equity - changes in shares of common stock (Details) - shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Changes in shares of common stock      
Beginning Balance, Common Stock 1,791,637,434 1,785,419,175 1,782,079,107
Treasury Stock, Shares, Beginning Balance 653,288,213 608,312,034 544,809,771
Repurchase of common stock 57,495,601 44,976,179 63,502,263
Distributed under benefit plans 4,014,769 6,218,259 3,340,068
Ending Balance, Common Stock 1,795,652,203 1,791,637,434 1,785,419,175
Treasury Stock, Shares, Ending Balance 710,783,814 653,288,213 608,312,034