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Represents the advance rate on accounts receivable advances term range one included by credit facilities amendment.

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Represents information about accounts receivable advances term range two included by credit facilities amendment.

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Maximum amount of stock repurchases in connection with the distribution limitations in fifth amendment related to repurchases of the Company’s stock.

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The maximum leverage ratio of the company before certain debt contingencies arise.

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Represents the distribution limitations, minimum percentage of aggregate funds available.

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Represents the distribution limitations, percentage of consolidated net income.

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Represents the distribution limitations, percentage of sum of borrowing bases.

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Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Incremental percentage increase (decrease) in the stated rate on a debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of the required periodic payments including both interest and principal payments.

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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Note F - Debt Facilities (Details Textual)							6 Months Ended	12 Months Ended			18 Months Ended	24 Months Ended
Note F - Debt Facilities (Details Textual)	Dec. 03, 2018 USD ($)	Mar. 29, 2018	Oct. 25, 2017 USD ($)	Dec. 12, 2016 USD ($)	Oct. 31, 2016	Dec. 15, 2015 USD ($)	Oct. 24, 2017 USD ($)	Apr. 30, 2019 USD ($)	Apr. 30, 2018 USD ($)	Apr. 30, 2017 USD ($)	Apr. 30, 2019 USD ($)	Apr. 30, 2019 USD ($)	Dec. 02, 2018 USD ($)	Feb. 28, 2016 USD ($)
Amortization of Debt Issuance Costs and Discounts, Total								$ 251,000	$ 260,000	$ 252,000
Debt Related Commitment Fees and Debt Issuance Costs								371,000	103,000
Debt Issuance Costs, Gross								556,000	$ 435,000		$ 556,000	$ 556,000
Long-term Debt, Total								194,000			194,000	194,000
Capital Lease Obligations, Total								839,000			839,000	839,000
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation								177,000			177,000	177,000
Assets Held under Capital Leases [Member]
Property, Plant and Equipment, Useful Life		3 years
Note Payable Related to the Property Purchase Agreement [Member]
Debt Instrument, Face Amount						$ 550,000
Debt Instrument, Periodic Payment, Total						$ 10,005
Debt Instrument, Interest Rate, Stated Percentage						3.50%
Revolving Credit Facility [Member]
Dividend Restrictions Maximum Aggregate Amount of Stock Repurchases			$ 50,000,000	$ 40,000,000
Line of Credit Facility, Maximum Borrowing Capacity	$ 215,000,000			200,000,000									$ 200,000,000	$ 172,500,000
Line of Credit Facility, Additional Borrowing Capacity, Accordion Feature				$ 50,000,000				$ 53,000,000			$ 53,000,000	$ 53,000,000
Debt Agreement, Accounts Receivable Advances, Term Range One, Rate				55.00%	50.00%
Debt Agreement, Accounts Receivable Advances, Term Range Two, Rate				50.00%	45.00%
Line of Credit Facility, Distribution Limitations Percentage of Sum of Borrowing Bases			20.00%				25.00%	20.00%				20.00%
Leverage Ratio, Maximum Threshold			1.75
Debt Instrument, Interest Rate, Effective Percentage								4.73%	4.25%		4.73%	4.73%
Line of Credit Facility, Distribution Limitations, Maximum Aggregate Amount of Stock Repurchases							$ 40,000,000				$ 50,000,000
Line of Credit Facility, Distribution Limitations Percentage of Consolidated Net Income								75.00%				75.00%
Line of Credit Facility Distribution Limitations Minimum Percentage of Aggregate Funds Available								12.50%				12.50%
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate								2.35%
Revolving Credit Facility [Member] \| Second Pricing Tier [Member]
Debt Instrument, Interest Rate, Increase (Decrease)			0.025%
Revolving Credit Facility [Member] \| Third Pricing Tier [Member]
Debt Instrument, Interest Rate, Increase (Decrease)			0.125%
Revolving Credit Facility [Member] \| Fourth Pricing Tier [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Interest Rate, Increase (Decrease)			3.00%
Revolving Credit Facility [Member] \| Second Amendment [Member]
Debt Instrument, Interest Rate, Increase (Decrease)	0.10%
Revolving Credit Facility [Member] \| Second Amendment [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	2.25%
Revolving Credit Facility [Member] \| Minimum [Member]
Debt Agreement, Accounts Receivable Advances, Term Range One				3 years 30 days
Debt Agreement, Accounts Receivable Advances, Term Range Two				3 years 210 days
Revolving Credit Facility [Member] \| Maximum [Member]
Debt Agreement, Accounts Receivable Advances, Term Range One				42 years
Debt Agreement, Accounts Receivable Advances, Term Range Two				5 years
Colonial Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 205,000,000												$ 190,000,000
ACM TCM Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 10,000,000