Acquisition | TS Allocation of Purchase Price (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Feb. 28, 2017	Jan. 31, 2018	Jan. 31, 2020	Jan. 31, 2019	Feb. 27, 2017
Business Acquisition [Line Items]
Goodwill			$ 973,257	$ 892,990
TS
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 1,000,000
Cash					$ 176,000
Accounts receivable					1,830,000
Inventories					239,000
Prepaid expenses and other current assets					100,000
Property and equipment, net					62,000
Goodwill					727,000
Intangible assets					919,000
Other assets, net					151,000
Total assets					4,204,000
Other current liabilities					1,169,000
Revolving credit loans and long-term debt					134,000
Other long-term liabilities					99,000
Total liabilities					1,402,000
Purchase price					$ 2,802,000
Customer Relationships [Member] | TS
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	$ 875,000	875,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	14 years
Trade Names [Member] | TS
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	$ 44,000	$ 44,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years