Goodwill | Schedule of Changes in Carrying Amounts of Goodwill (Details) $ in Thousands	9 Months Ended
	Oct. 31, 2017 USD ($)
Goodwill
Balance as of January 31, 2017	$ 199,021
Goodwill acquired during the year	609,427	[1]
Foreign currency translation adjustment	33,775
Balance as of October 31, 2017	842,223
Americas
Goodwill
Balance as of January 31, 2017	19,559
Goodwill acquired during the year	444,837	[1]
Foreign currency translation adjustment	2,616
Balance as of October 31, 2017	467,012
Europe
Goodwill
Balance as of January 31, 2017	179,462
Goodwill acquired during the year	153,656	[1]
Foreign currency translation adjustment	30,324
Balance as of October 31, 2017	363,442
Asia-Pacific
Goodwill
Balance as of January 31, 2017	0
Goodwill acquired during the year	10,934	[1]
Foreign currency translation adjustment	835
Balance as of October 31, 2017	$ 11,769

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