LONG (Details)			6 Months Ended		6 Months Ended			6 Months Ended		6 Months Ended		6 Months Ended			6 Months Ended						6 Months Ended
	Jun. 30, 2012 USD ($)	Dec. 31, 2011 USD ($)	Jun. 30, 2012 2003 multi-currency uncommitted shelf facility, U.S. dollar denominated 1 [Member] USD ($)	Dec. 31, 2011 2003 multi-currency uncommitted shelf facility, U.S. dollar denominated 1 [Member] USD ($)	Jun. 30, 2012 2003 multi-currency uncommitted shelf facility, U.S. dollar denominated 2 [Member] USD ($)	Dec. 31, 2011 2003 multi-currency uncommitted shelf facility, U.S. dollar denominated 2 [Member] USD ($)	Jun. 30, 2012 2003 multi-currency uncommitted shelf facility, total U.S. dollar-denominated debt [Member] USD ($)	Jun. 30, 2012 2003 multi-currency uncommitted shelf facility, Japanese yen denominated 1 [Member] JPY (¥)	Dec. 31, 2011 2003 multi-currency uncommitted shelf facility, Japanese yen denominated 1 [Member] JPY (¥)	Jun. 30, 2012 2003 multi-currency uncommitted shelf facility, Japanese yen denominated 2 [Member] JPY (¥)	Dec. 31, 2011 2003 multi-currency uncommitted shelf facility, Japanese yen denominated 2 [Member] JPY (¥)	Jun. 30, 2012 2003 multi-currency uncommitted shelf facility, Japanese yen denominated 3 [Member] JPY (¥)	Dec. 31, 2011 2003 multi-currency uncommitted shelf facility, Japanese yen denominated 3 [Member] JPY (¥)	Jun. 30, 2012 2003 multi-currency uncommitted shelf facility, total Japanese yen-denominated debt [Member] USD ($)	Jun. 30, 2012 2010 committed loan, U.S. dollar denominated [Member] USD ($)	Jun. 30, 2012 2010 committed loan, U.S. dollar denominated [Member] JPY (¥)	Dec. 31, 2011 2010 committed loan, U.S. dollar denominated [Member] USD ($)	Jun. 30, 2012 2004 revolving credit facility [Member] USD ($)	Dec. 31, 2011 2004 revolving credit facility [Member] USD ($)	Jun. 30, 2012 2009 uncommitted multi-currency shelf facility [Member] USD ($)	Jun. 30, 2012 Multi Currency Uncommitted Shelf Facility Japanese Yen Denominated 2 Member [Member] JPY (¥)
Debt Instrument [Line Items]
Original principal amount - facilities			$ 40,000,000		$ 20,000,000			¥ 3.100000000		¥ 2.300000000		¥ 2.200000000				¥ 30.000000000				$ 0	¥ 8.000000000
Balance - facilities			28,600,000	28,600,000	14,300,000	17,100,000		0.900000000	1.300000000	1.900000000	1.900000000	1.500000000	1.900000000		21,000,000		24,000,000	0			8.000000000
Interest rate - facilities (in hundredths)			6.20%		6.20%			1.70%		2.60%		3.30%						0.00%			1.70%
Repayment terms			Notes due July 2016 with annual principal payments that began in July 2010.		Notes due January 2017 with annual principal payments that began in January 2011.			Notes due April 2014 with annual principal payments that began in April 2008.		Notes due September 2017 with annual principal payments that began in September 2011.		Notes due January 2017 with annual principal payments that began in January 2011.			Amortizes at $1.5 million per quarter.	Amortizes at $1.5 million per quarter.					Notes due May 2022 with annual principal payments that begin in May 2016.
Interest rate description - other borrowings															Variable 30 day: 1.24%	Variable 30 day: 1.24%
Current portion of long-term debt	$ 28,100,000	$ 28,608,000					$ 8,600,000							$ 13,500,000	$ 6,000,000