Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
3.24% $100 Million Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Line Of Credit Facility Forecasted Borrowing Amount	$ 100,000
Derivative, Fixed Interest Rate	3.24%
Interest Rate Cash Flow Hedge Derivative at Fair Value, Net	4,668		5,312
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss)	(125)	(61)
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedge, Net of Tax, Accumulated Other Comprehensive Income (Loss)	(77)	(37)
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	(768)	(755)
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net, Net of Tax	(472)	(465)
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	(3,069)
Gain (Loss) on Interest Rate Cash Flow Hedge Ineffectiveness	0	0
2.52% $50 Million Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Line Of Credit Facility Forecasted Borrowing Amount	50,000
Derivative, Fixed Interest Rate	2.52%
Interest Rate Cash Flow Hedge Asset at Fair Value	565		1,269
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss)	(703)
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedge, Net of Tax, Accumulated Other Comprehensive Income (Loss)	(432)
Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	78,194		78,200
Foreign Currency Cash Flow Hedge Asset at Fair Value	469		268
Foreign Currency Cash Flow Hedge Liability at Fair Value	0		103
Unrealized Gain (Loss) on Foreign Currency Derivatives, Net, before Tax	260	(787)
Unrealized Gain (Loss) on Foreign Currency Derivatives, Net, After Tax	207	(626)
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	40	(475)
Foreign Currency Cash Flow Hedge Gain Loss Reclassified To Earnings, Net, After Tax	32	(378)
Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months	454
Gain (Loss) on Interest Rate Cash Flow Hedge Ineffectiveness	0	0
Foreign Exchange Forward [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	173,929		180,321
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	235		719
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	775		355
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	$ (246)	$ (2,225)