Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Assets:
Cash Equivalents	$ 15,500	$ 13,600
Fair Value, Measurements, Recurring [Member]
Assets:
Cash Equivalents	15,478	13,619
Foreign currency forward contracts	987	545
Total Assets at Fair Value	16,465	14,164
Liabilities:
Interest rate swap agreements	8,856	9,175
Foreign currency forward contracts	307	480
Total Liabilities at Fair Value	9,163	9,655
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Cash Equivalents	0	0
Foreign currency forward contracts	0	0
Total Assets at Fair Value	0	0
Liabilities:
Interest rate swap agreements	0	0
Foreign currency forward contracts	0	0
Total Liabilities at Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Cash Equivalents	15,478	13,619
Foreign currency forward contracts	987	545
Total Assets at Fair Value	16,465	14,164
Liabilities:
Interest rate swap agreements	8,856	9,175
Foreign currency forward contracts	307	480
Total Liabilities at Fair Value	9,163	9,655
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets:
Cash Equivalents	0	0
Foreign currency forward contracts	0	0
Total Assets at Fair Value	0	0
Liabilities:
Interest rate swap agreements	0	0
Foreign currency forward contracts	0	0
Total Liabilities at Fair Value	$ 0	$ 0