Income Taxes - Current and Deferred Income Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2026	Jan. 31, 2025	Jan. 31, 2024
Current:
Federal	$ 342,568	$ 323,625	$ 257,913
State	52,041	52,186	44,457
Foreign	22,493	20,086	9,159
Total current income tax expense	417,102	395,897	311,529
Deferred:
Federal	100,104	(78,476)	(88,110)
State	2,416	(12,875)	(20,201)
Foreign	2,515	800	(8,368)
Total deferred income tax expense	105,035	(90,551)	(116,679)
Total provision for income taxes	$ 522,137	$ 305,346	$ 194,850