Shareholders' Equity Components of AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Components of AOCI [Line Items]
Beginning Accumulated Other Comprehensive Income (Loss), Net of Tax	$ 43,786	$ 288,292	$ (74,542)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(42,211)	(239,433)	362,834
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(111)	(5,073)	0
Ending Accumulated Other Comprehensive Income (Loss), Net of Tax	1,464	43,786	288,292
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest [Member]
Components of AOCI [Line Items]
Beginning Accumulated Other Comprehensive Income (Loss), Net of Tax	43,786	288,292	(74,542)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(42,337)	(239,433)	362,834
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	(5,073)	0
Ending Accumulated Other Comprehensive Income (Loss), Net of Tax	1,449	43,786	288,292
Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest [Member]
Components of AOCI [Line Items]
Beginning Accumulated Other Comprehensive Income (Loss), Net of Tax	0	0	0
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	126	0	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(111)	0	0
Ending Accumulated Other Comprehensive Income (Loss), Net of Tax	$ 15	$ 0	$ 0