Long-Term Debt and Related Matters (Schedule Of Long-Term Debt Table) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Debt Instrument
Revolving credit facility with an interest rate of 4.78% at December 31, 2017 and 4.22% at December 31, 2016	$ 128,470		$ 127,073
Term loan payable in quarterly installments through January 1, 2020 with an interest rate of 3.92% at December 31, 2016	0		30,000
Total	129,966		159,565
Less current maturities	656		10,386
Long-term portion	$ 129,310		$ 149,179
Interest rate on credit facility	4.78%		4.22%
Interest rate on accounts payable			3.92%
Finance Agreement
Debt Instrument
Lease obligations payable in installments	$ 0		$ 534
Interest rate on term loan		3.00%
Lease Obligation
Debt Instrument
Lease obligations payable in installments	$ 1,496		$ 1,958
Interest rate on debt obligation	3.21%		3.10%

Reflects the effective interest rate as of the balance sheet date on interest-bearing trade payables.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 25
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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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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The effective interest rate at the end of the reporting period.

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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