Cash Discounts And Doubtful Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reserve for Cash Discount and Allowances for Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	$ 6,837	$ 6,868	$ 7,764
Provision (Charged to Expense)	29,087	24,971	25,607
Deductions	(28,851)	(25,002)	(26,503)
Ending Balance	7,073	6,837	6,868
Allowance for cash discounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	1,560	1,411	1,498
Provision (Charged to Expense)	25,318	22,943	21,228
Deductions	(25,114)	(22,794)	(21,315)
Ending Balance	1,764	1,560	1,411
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	5,277	5,457	6,266
Provision (Charged to Expense)	3,769	2,028	4,379
Deductions	(3,737)	(2,208)	(5,188)
Ending Balance	$ 5,309	$ 5,277	$ 5,457

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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- Definition

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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