Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Accumulated Other Comprehensive Income Loss [Line Items]
Interest expense	$ 1,155	$ 1,625	$ 3,425	$ 4,635
Selling, general and administrative expenses	6,953	7,123	21,449	21,270
Income tax provision	1,270	1,194	3,931	3,925
Reclassification Out Of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Net of tax	86		254
Gains and Losses on Cash Flow Hedges [Member] | Interest Rate Contract [Member] | Reclassification Out Of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Interest expense	28		74
Income tax provision	(12)		(30)
Net of tax	16		44
Amortization of Benefit Pension Items [Member] | Reclassification Out Of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Selling, general and administrative expenses	117		349
Income tax provision	(47)		(139)
Net of tax	70		210
Amortization of Benefit Pension Items [Member] | Prior Service Costs [Member] | Reclassification Out Of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Selling, general and administrative expenses	236		708
Amortization of Benefit Pension Items [Member] | Actuarial Gains (Losses) [Member] | Reclassification Out Of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Selling, general and administrative expenses	$ (119)		$ (359)