Note 8. Employee Benefit Plans (Detail) - Pension And Benefit Plan Amounts Included In Accumulated Other Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Unamortized prior service cost	$ (7,754)	$ (1,653)	$ 6,006
Pension Plans, Defined Benefit [Member]
Unamortized net (gain)/loss	28,450
Unamortized prior service cost	2,297
Other Postretirement Benefit Plans, Defined Benefit [Member]
Unamortized net (gain)/loss	(488)
Unamortized prior service cost	$ 219