Consolidated Statement Of Income - USD ($)
shares in Thousands, $ in Thousands
 3 Months Ended 6 Months Ended
Jul. 31, 2018
Jul. 31, 2017
Jul. 31, 2018
Jul. 31, 2017
Income Statement [Abstract]        
Revenues $ 8,886,101 $ 8,092,353 $ 17,434,420 $ 15,115,973
Cost of Goods and Services Sold 8,359,071 7,576,762 16,384,273 14,143,294
Gross profit 527,030 515,591 1,050,147 972,679
Selling, general and administrative expenses 415,319 410,598 837,680 763,230
Acquisition, integration and restructuring expenses 13,297 30,117 46,522 72,183
Legal settlements and other, net (5,234) (28,655) (8,199) (41,343)
Gain on disposal of subsidiary 6,717 0 6,717 0
Operating expenses 416,665 412,060 869,286 794,070
Operating income 110,365 103,531 180,861 178,609
Interest expense 28,053 28,272 53,975 59,280
Other expense (income), net 901 284 2,818 (131)
Income before income taxes 81,411 74,975 124,068 119,460
Provision for income taxes 5,545 27,516 14,503 41,347
Net income $ 75,866 $ 47,459 $ 109,565 $ 78,113
Earnings per share:        
Basic $ 1.97 $ 1.24 $ 2.86 $ 2.07
Diluted $ 1.97 $ 1.24 $ 2.84 $ 2.06
Weighted average common shares outstanding:        
Basic 38,428 38,174 38,356 37,720
Diluted 38,566 38,388 38,565 37,935