Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Fixed interest rate related to the interest rate derivative.

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Financing Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
Financing Arrangements (Details) - USD ($) $ in Thousands	Jan. 31, 2017	Apr. 30, 2016	Jan. 31, 2016	Jul. 31, 2016	Jul. 31, 2015	Oct. 31, 2016	Oct. 30, 2015	Apr. 29, 2015	Feb. 24, 2014
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				5.09%	4.23%
Letters of Credit Outstanding, Amount	$ 5,080
Collateral Agreement	65.00%
Long-term Debt	$ 234,147
Long-term Debt, Excluding Current Maturities	$ 236,660					$ 256,922
Derivatives, Interest Rate Swap, Maturity	5 years
Other Comprehensive Loss, Unrealized Loss on Derivatives Arising During Period, Net of Tax	$ 1,119		$ (480)
Interest Expense	4,812		4,352
Lender Group Two [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Increase Minimum								$ 25,000
Line of Credit Increase Maximum								100,000
Line of Credit Facility, Maximum Borrowing Capacity								360,000
Line of Credit, Committed Reductions								$ 30,000
Line of Credit Facility, Increase (Decrease) for Period, Description		$ 5,000
Line of Credit Facility, Current Borrowing Capacity		$ 355,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 117,020
Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.05%
Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.77%
Maximum [Member] \| Lender Group Two [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Capacity Available for Debt Issuance							$ 40,000
Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases							$ 50,000
Insurance Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.96%
Debt Instrument, Periodic Payment	$ 95
Short-term Debt	379					661
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	379
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt	232,900					252,900
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 0
Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.47%
Debt Instrument, Periodic Payment	$ 44
Long-term Debt	868					996
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	516
Long-term Debt, Excluding Current Maturities	352
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt	4,273					$ 4,388
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	865
Interest Rate Swap [Member] \| Lender Group Two [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Derivative, Notional Amount									$ 75,000
Derivative, Fixed Interest Rate									2.74%
Derivative, Notional Amount, Amount Per Base									$ 25,000
Derivative, Incremental Amounts									$ 25,000
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Lender Group Two [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				1.50%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member] \| Lender Group Two [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				4.00%
Base Rate [Member] \| Minimum [Member] \| Lender Group Two [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				0.50%
Base Rate [Member] \| Maximum [Member] \| Lender Group Two [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				3.00%
Fixed Rate Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	1,247
Cash Flow Hedging [Member] \| Interest Rate Swap [Member] \| Lender Group Two [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Interest Expense	$ 418		$ 334