Debt (Narrative) (Details) - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Total debt	$ 173,079,000	$ 144,083,000
Unsecured Debt \| Amended and Restated Revolving Credit Agreement \| Bank revolving credit facility
Debt Instrument [Line Items]
Aggregate commitments	250,000,000
Maximum amount of additional aggregate commitments (Up to $50,000,000)	50,000,000
Total debt	173,000,000
Available borrowings	75,418,000
Unsecured Debt \| Amended and Restated Revolving Credit Agreement \| Standby Letters of Credit
Debt Instrument [Line Items]
Amount of capacity	$ 1,582,000

Debt Instrument Covenant Compliance Aggregate Commitments

No definition available.

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- Definition

Debt Instrument Covenant Compliance Maximum Increase Amount Of Aggregate Commitments

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for financing purchases of goods acquired for inventory or imminent delivery to a customer.

+ References

No definition available.

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of long-term debt and capital lease obligations including current maturities.

+ References

No definition available.

+ Details

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