Intangible assets and goodwill (Schedule of intangible assets) (Details) - USD ($) $ in Thousands	Oct. 31, 2020	Jan. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 947,971	$ 879,597
Accumulated amortization	(172,276)	(98,851)
Total amortizable intangible assets, net	775,695	780,746
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Total intangible assets, net	776,311	783,279
In Process Research and Development
Indefinite-lived Intangible Assets [Line Items]
Acquired in process software development costs	616	2,533
Software and software development costs
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	116,206	76,221
Acquired HSA portfolios
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	121,159	92,770
Acquired customer relationships
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	601,381	601,381
Acquired developed technology
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	96,925	96,925
Acquired trade names
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 12,300	$ 12,300