Leases - Lease assets and liabilities (Details) - USD ($) $ in Thousands	Jul. 31, 2022	Jan. 31, 2022	Jul. 31, 2021
Assets and Liabilities, Lessee [Abstract]
Operating lease assets	$ 209,000	$ 169,595	$ 172,916
Classification of operating lease assets	Operating lease assets
Current operating lease liabilities	$ 49,734	42,763	43,119
Classification current operating lease liabilities	Current operating lease liabilities
Noncurrent operating lease liabilities	$ 179,247	142,868	147,119
Classification of noncurrent operating liabilities	Noncurrent operating lease liabilities
Total lease liabilities	$ 228,981	$ 185,631	$ 190,238