Business And Summary Of Significant Accounting Policies | Recently Adopted Accounting Standards (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended 12 Months Ended
Jul. 31, 2018
Jan. 31, 2018
Oct. 31, 2017
Jul. 31, 2017
Apr. 30, 2017
Jul. 31, 2018
Jul. 31, 2017
Jan. 31, 2018
New Accounting Pronouncement                
Net sales $ 8,886,101 $ 10,033,397 $ 8,448,471 $ 8,092,353 $ 7,023,620 $ 17,434,420 $ 15,115,973 $ 33,597,841
Cost of products sold 8,359,071 9,416,536 7,922,390 7,576,762 6,566,532 16,384,273 14,143,294 31,482,220
Accounts receivable, net 5,200,039 6,035,716       5,200,039   6,035,716
Inventories 3,022,673 2,965,521       3,022,673   2,965,521
Prepaid expenses and other assets 383,191 403,548       383,191   403,548
Accounts payable 6,233,180 6,962,193       6,233,180   6,962,193
Accrued expenses and other liabilities $ 1,016,496 1,169,986       $ 1,016,496   1,169,986
Calculated under Revenue Guidance in Effect before Topic 606 | Accounting Standards Update 2014-09                
New Accounting Pronouncement                
Net sales   11,092,529 9,135,728 8,882,691 7,664,063   16,546,754 36,775,011
Cost of products sold   10,475,668 $ 8,609,647 8,367,100 $ 7,206,975   15,574,075 34,659,390
Accounts receivable, net   5,783,666           5,783,666
Inventories   3,065,218           3,065,218
Prepaid expenses and other assets   288,178           288,178
Accounts payable   6,947,282           6,947,282
Accrued expenses and other liabilities   917,174           917,174
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09                
New Accounting Pronouncement                
Net sales       (790,338)     (1,430,781)  
Cost of products sold       $ (790,338)     $ (1,430,781)  
Accounts receivable, net   252,050           252,050
Inventories   (99,697)           (99,697)
Prepaid expenses and other assets   115,370           115,370
Accounts payable   14,911           14,911
Accrued expenses and other liabilities   $ 252,812           $ 252,812