Pension and Postretirement Benefits (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net periodic benefit cost of pension and post retirement benefit plans
Net periodic benefit cost	$ 597,000
Pension Plans [Member]
Net periodic benefit cost of pension and post retirement benefit plans
Service cost	104,000	121,000	145,000
Interest cost	1,150,000	1,189,000	1,242,000
Expected return on plan assets	(406,000)	(563,000)	(588,000)
Amortization of prior service credit			41,000
Recognized net actuarial loss	491,000	457,000	572,000
Net periodic benefit cost	1,339,000	1,204,000	1,412,000
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive income
Net actuarial loss	1,942,000	1,589,000	1,190,000
Reversal of amortization item
Net actuarial loss	(491,000)	(457,000)	(572,000)
Prior service cost			(41,000)
Total recognized in other comprehensive income	1,451,000	1,132,000	577,000
Total recognized in net periodic benefit cost and other comprehensive income	2,790,000	2,336,000	1,989,000
Postretirement Benefit Plans [Member]
Net periodic benefit cost of pension and post retirement benefit plans
Service cost	146,000	128,000	130,000
Interest cost	814,000	868,000	1,039,000
Expected return on plan assets	(74,000)	(135,000)	(160,000)
Amortization of prior service credit	(1,113,000)	(1,277,000)	(1,171,000)
Recognized net actuarial loss	547,000	533,000	608,000
Net periodic benefit cost	320,000	117,000	446,000
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive income
Net actuarial loss	224,000	24,000	421,000
Prior service credit			(1,197,000)
Reversal of amortization item
Net actuarial loss	(547,000)	(533,000)	(608,000)
Prior service cost	1,113,000	1,277,000	1,171,000
Total recognized in other comprehensive income	790,000	768,000	(213,000)
Total recognized in net periodic benefit cost and other comprehensive income	1,110,000	885,000	233,000
Foreign Pension Plans [Member]
Net periodic benefit cost of pension and post retirement benefit plans
Service cost	491,000	366,000	304,000
Interest cost	737,000	729,000	780,000
Expected return on plan assets	(622,000)	(665,000)	(597,000)
Recognized net actuarial loss	201,000	73,000	54,000
Net periodic benefit cost	807,000	503,000	541,000
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive income
Net actuarial loss	(958,000)	(1,936,000)	(299,000)
Reversal of amortization of net actuarial loss	(201,000)	(73,000)	(54,000)
Reversal of amortization item
Total recognized in other comprehensive income	757,000	1,863,000	245,000
Total recognized in net periodic benefit cost and other comprehensive income	$ 1,564,000	$ 2,366,000	$ 786,000