Commitments and Contingencies (Details) - Charitable Gift [Member] - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Apr. 30, 2018	Jul. 31, 2019	Jul. 31, 2018
Loss Contingencies [Line Items]
Long-term Purchase Commitment, Amount				$ 5,000
Loss Contingency Accrual	$ 3,261			3,261
Cumulative Loss Contingency Accrual, Payments				1,430
Selling, General and Administrative Expenses [Member]
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period	0	$ 0	$ 4,503	0	$ 4,503
Accrued Liabilities [Member]
Loss Contingencies [Line Items]
Loss Contingency, Accrual, Current	704			704
Other Noncurrent Liabilities [Member]
Loss Contingencies [Line Items]
Loss Contingency, Accrual, Noncurrent	$ 2,557			$ 2,557