Long-Term Debt and Borrowings Under Short-Term Credit Agreements Long-Term Debt (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Total Long-Term Debt and Capital Lease Obligations	$ 11,995,000	$ 51,835,000
Less current portion	(10,005,000)	(41,490,000)
Long-term Debt and Capital Lease Obligations	1,990,000	10,345,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2013	10,005,000
2014	1,446,000
2015	412,000
2016	132,000
2017	0
After 2017	0
Long-term debt	11,995,000
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities		27,715,000
Other Noncontrolling Interests		1,005,000
Debt Instrument, Collateral, Property Net Book Value	0	16,847,000
Secured Debt | Variable-rate lease arrangement, secured by facilities, due July 2013
Debt Instrument [Line Items]
Total Long-Term Debt and Capital Lease Obligations	0	27,715,000
Unsecured Debt | Unsecured 6.65% Senior Note Through June 2013
Debt Instrument [Line Items]
Total Long-Term Debt and Capital Lease Obligations	3,750,000	11,250,000
Unsecured Debt | Unsecured 6.59% Senior Note Through April 2013
Debt Instrument [Line Items]
Total Long-Term Debt and Capital Lease Obligations	3,636,000	7,273,000
Capital Lease Obligations | Capital Leases, Secured by Equiptment, Variable Rates 2.38%-4.97%, Variable Maturities
Debt Instrument [Line Items]
Total Long-Term Debt and Capital Lease Obligations	$ 4,609,000	$ 5,597,000