Note 5. Shareholders' Equity (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax, beginning	$ (354,409)	$ (269,531)
Other comprehensive income (loss) before reclassifications	(3,064)	122
Other comprehensive income (loss) before reclassifications	(3,064)	122
Amounts reclassified from accumulated other comprehensive loss	1,941	1,054
Accumulated other comprehensive income (loss), net of tax, ending	(355,532)	(268,355)
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax, beginning	(3,155)	(424)
Other comprehensive income (loss) before reclassifications	(3,064)	122
Amounts reclassified from accumulated other comprehensive loss	0	0
Accumulated other comprehensive income (loss), net of tax, ending	(6,219)	(302)
Employee Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax, beginning	(351,254)	(269,107)
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive loss	1,941	1,054
Accumulated other comprehensive income (loss), net of tax, ending	$ (349,313)	$ (268,053)