Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Oct. 31, 2018	Jan. 31, 2018	Oct. 31, 2017	Oct. 31, 2018	Oct. 31, 2017
Schedule of tax impact from settlement [Line Items]
US Tax Act Impact	$ 71,400	$ 95,400
Other Tax Expense (Benefit)	(5,500)			$ (6,100)
Other Selling, General and Administrative Expense_Indemnification	5,500			6,100
US Tax Act Impact - Transition Tax	$ 24,000	101,100		$ 24,000
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount		$ (5,700)
Effective Income Tax Rate Reconciliation, Percent	2.00%		32.10%	7.00%	33.80%
Provision for income taxes	$ 2,306		$ 17,617	$ 16,809	$ 58,964
TS
Schedule of tax impact from settlement [Line Items]
Deferred Other Tax Expense (Benefit)	$ (200)			$ (13,000)