Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 10,954	$ 14,688	$ 14,763
Additions Charged to Costs and Expenses	29,424	29,858	30,626
Deductions	29,511	33,592	30,701
Balance at End of Period	10,867	10,954	14,688
Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	318	308	198
Additions Charged to Costs and Expenses	198	10	115
Deductions	324	0	5
Balance at End of Period	192	318	308
Cash Discounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	259	573	40
Additions Charged to Costs and Expenses	25,207	26,620	27,671
Deductions	25,225	26,934	27,138
Balance at End of Period	241	259	573
Deferred Tax Valuation Allowance [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	6,310	9,752	10,290
Additions Charged to Costs and Expenses	0	0	332
Deductions	296	3,442	870
Balance at End of Period	6,014	6,310	9,752
Sales Returns [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	4,067	4,055	4,235
Additions Charged to Costs and Expenses	4,019	3,228	2,508
Deductions	3,666	3,216	2,688
Balance at End of Period	$ 4,420	$ 4,067	$ 4,055