Commitments and Contingencies Commitments (Details) - Charitable Gift - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Apr. 30, 2018	Jan. 31, 2019
Loss Contingencies [Line Items]
Long-term purchase commitment, amount		$ 5,000
Loss Contingency, Loss in Period	$ 4,503	4,503
Loss Contingency Accrual		3,199
Loss Contingency Accrual, Payments		(1,430)
Selling, General and Administrative Expenses
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period		4,503
Other Nonoperating Income (Expense)
Loss Contingencies [Line Items]
Interest Expense, Loss Contingency Accrual Period Increase		127
Accrued Liabilities
Loss Contingencies [Line Items]
Loss Contingency, Accrual, Current		691
Other Noncurrent Liabilities
Loss Contingencies [Line Items]
Loss Contingency, Accrual, Noncurrent		$ 2,509