Goodwill | Schedule of Changes in Carrying Amounts of Goodwill (Details) $ in Thousands	6 Months Ended
	Jul. 31, 2017 USD ($)
Goodwill
Balance as of January 31, 2017	$ 199,021
Goodwill acquired during the year	615,727	[1]
Foreign currency translation adjustment	39,019
Balance as of July 31, 2017	853,767
Americas
Goodwill
Balance as of January 31, 2017	19,559
Goodwill acquired during the year	450,719	[1]
Foreign currency translation adjustment	2,266
Balance as of July 31, 2017	472,544
Europe
Goodwill
Balance as of January 31, 2017	179,462
Goodwill acquired during the year	153,818	[1]
Foreign currency translation adjustment	35,658
Balance as of July 31, 2017	368,938
Asia-Pacific
Goodwill
Balance as of January 31, 2017	0
Goodwill acquired during the year	11,190	[1]
Foreign currency translation adjustment	1,095
Balance as of July 31, 2017	$ 12,285

[1] Amounts based on preliminary purchase price allocation related to the acquisition of TS.