Goodwill | Schedule of Changes in Carrying Amounts of Goodwill (Details) $ in Thousands	3 Months Ended
	Apr. 30, 2017 USD ($)
Goodwill
Balance as of January 31, 2017	$ 199,021
Goodwill acquired during the year	492,606	[1]
Foreign currency translation adjustment	6,815
Balance as of April 30, 2017	698,442
Americas
Goodwill
Balance as of January 31, 2017	19,559
Goodwill acquired during the year	362,751	[1]
Foreign currency translation adjustment	(67)
Balance as of April 30, 2017	382,243
Europe
Goodwill
Balance as of January 31, 2017	179,462
Goodwill acquired during the year	122,503	[1]
Foreign currency translation adjustment	6,219
Balance as of April 30, 2017	308,184
Asia-Pacific
Goodwill
Balance as of January 31, 2017	0
Goodwill acquired during the year	7,352	[1]
Foreign currency translation adjustment	663
Balance as of April 30, 2017	$ 8,015

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