Consolidated Statement Of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2018	Oct. 31, 2017
Income Statement [Abstract]
Revenues	$ 9,340,029	$ 8,448,471	$ 26,774,449	$ 23,564,444
Cost of Goods and Services Sold	8,783,425	7,922,390	25,167,698	22,065,684
Gross profit	556,604	526,081	1,606,751	1,498,760
Selling, general and administrative expenses	396,675	416,766	1,234,355	1,179,996
Acquisition, integration and restructuring expenses	20,277	29,748	66,799	101,931
Legal settlements and other, net	(7,207)	0	(15,406)	(41,343)
Gain on disposal of subsidiary	(29)	0	(6,746)	0
Operating expenses	409,716	446,514	1,279,002	1,240,584
Operating income	146,888	79,567	327,749	258,176
Interest expense	25,405	25,925	79,380	85,205
Other expense (income), net	4,961	(1,243)	7,779	(1,374)
Income before income taxes	116,522	54,885	240,590	174,345
Provision for income taxes	2,306	17,617	16,809	58,964
Net income	$ 114,216	$ 37,268	$ 223,781	$ 115,381
Earnings per share:
Basic	$ 2.98	$ 0.98	$ 5.83	$ 3.05
Diluted	$ 2.96	$ 0.97	$ 5.80	$ 3.03
Weighted average common shares outstanding:
Basic	38,358	38,186	38,357	37,877
Diluted	38,526	38,433	38,559	38,105