Acquisition, Integration and Restructuring Expenses | Global Business Optimization Program (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018
Restructuring Cost and Reserve
Acquisition, integration and restructuring expenses	$ 5,209	$ 13,297	$ 11,430	$ 46,522
Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges	5,209	12,735	11,430	18,343
Restructuring and Related Cost, Cost Incurred to Date	53,971		53,971
Restructuring Charges | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges			11,430
Employee Severance | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges	3,187	5,605	7,334	8,874
Restructuring and Related Cost, Cost Incurred to Date	33,761		33,761
Professional services | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges	2,022	7,130	4,096	9,469
Restructuring and Related Cost, Cost Incurred to Date	20,210		20,210
Minimum | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring and Related Cost, Expected Cost	70,000		70,000
Maximum | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring and Related Cost, Expected Cost	80,000		80,000
Europe
Restructuring Cost and Reserve
Acquisition, integration and restructuring expenses		13,300		31,300
Restructuring Charges	3,229		6,300
Europe | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges		6,125		10,882
Europe | Restructuring Charges
Restructuring Cost and Reserve
Acquisition, integration and restructuring expenses		3,700		11,100
Europe | Minimum | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring and Related Cost, Expected Cost	40,000		40,000
Europe | Maximum | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring and Related Cost, Expected Cost	45,000		45,000
Americas
Restructuring Cost and Reserve
Acquisition, integration and restructuring expenses		(900)		13,100
Restructuring Charges	1,341		4,252
Americas | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges		6,485		7,336
Americas | Restructuring Charges
Restructuring Cost and Reserve
Acquisition, integration and restructuring expenses		100		3,500
Americas | Minimum | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring and Related Cost, Expected Cost	30,000		30,000
Americas | Maximum | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring and Related Cost, Expected Cost	35,000		35,000
Asia-Pacific | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges	$ 639	$ 125	$ 925	$ 125