v3.24.0.1
Capital Stock: (Schedule of Common Stock) (Details) - shares
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Capital Stock [Roll Forward]      
Shares issued, beginning of period (in shares) 2,109,316,331    
Shares repurchased, beginning of period (in shares) (559,098,620)    
Shares issued, end of period (in shares) 2,109,316,331 2,109,316,331  
Shares repurchased, end of period (in shares) (556,891,800) (559,098,620)  
Shares Issued      
Capital Stock [Roll Forward]      
Shares issued, beginning of period (in shares) 2,109,316,331 2,109,316,331 2,109,316,331
Shares issued, end of period (in shares) 2,109,316,331 2,109,316,331 2,109,316,331
Shares Repurchased      
Capital Stock [Roll Forward]      
Shares repurchased, beginning of period (in shares) (559,098,620) (559,146,338) (551,942,600)
Repurchase of shares (in shares) 0 (1,966,730) (8,514,629)
Issuance of stock awards (in shares) 2,206,820 2,014,448 1,310,891
Shares repurchased, end of period (in shares) (556,891,800) (559,098,620) (559,146,338)
Shares Outstanding      
Capital Stock [Roll Forward]      
Shares outstanding, beginning of period (in shares) 1,550,217,711 1,550,169,993 1,557,373,731
Repurchase of shares (in shares) 0 (1,966,730) (8,514,629)
Issuance of stock awards (in shares) 2,206,820 2,014,448 1,310,891
Shares outstanding, end of period (in shares) 1,552,424,531 1,550,217,711 1,550,169,993