Pension and Other Postretirement Benefits (Details 6) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Pension Benefits [Member]
Components of accumulated other comprehensive income:
Net actuarial loss		$ 68,463
Net prior service credit		(281)
Total		68,182
Changes in accumulated other comprehensive income:
Net actuarial loss, beginning of year	68,463	58,915
Amortization cost		(6,030)
Liability loss		10,855
Asset loss		4,096
Currency impact		627
Net actuarial loss, end of year		68,463
Prior service cost, beginning of year	281	(679)
Amortization cost		63
Plan amendment		356
Currency impact		(21)
Prior service cost, end of year		(281)
Expected 2012 amortization:
Amortization of prior service cost	(54)
Amortization of net losses	(6,088)
Total	6,034
Other Benefits [Member]
Components of accumulated other comprehensive income:
Net actuarial loss		11,846
Net prior service credit		(488)
Total		11,358
Changes in accumulated other comprehensive income:
Net actuarial loss, beginning of year	11,846	8,117
Amortization cost		(386)
Liability loss		4,262
Currency impact		(147)
Net actuarial loss, end of year		11,846
Prior service cost, beginning of year	488	(608)
Amortization cost		116
Currency impact		4
Prior service cost, end of year		(488)
Expected 2012 amortization:
Amortization of prior service cost	(109)
Amortization of net losses	(810)
Total	$ 701