Acquisition, Integration and Restructuring Expenses | Global Business Optimization Program (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Restructuring Cost and Reserve
Acquisition, integration and restructuring expenses	$ 4,647	$ 20,277	$ 16,077	$ 66,799
Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges	2,881	13,124	14,311	31,467
Restructuring and Related Cost, Cost Incurred to Date	56,852		56,852
Restructuring Charges | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges			14,311
Employee Severance | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges	1,851	8,741	9,185	17,615
Restructuring and Related Cost, Cost Incurred to Date	35,612		35,612
Professional services | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges	1,030	4,383	5,126	13,852
Restructuring and Related Cost, Cost Incurred to Date	21,240		21,240
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		13,100		44,400
Restructuring Charges	1,000		7,200
Europe | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges	975	10,099	7,228	20,981
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		6,000		19,000
Restructuring Charges	3,500		7,800
Americas | Global Business Optimization Program
Restructuring Cost and Reserve
Restructuring Charges	1,902	2,502	6,154	9,838
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	$ 4	$ 523	$ 929	$ 648