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