Income Taxes (Schedule Of Components Of Pretax Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Income Tax Disclosure [Abstract]
United States	$ 92,067	$ 195,219	$ 100,166
Foreign	164,694	187,199	139,018
Income before income taxes	$ 256,761	$ 382,418	$ 239,184