Note 7. Income Taxes (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended					9 Months Ended
	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2012 Expiring 2012-2030 [Member]	Sep. 30, 2012 Expiring In 2012 [Member]	Sep. 30, 2012 Expiring 2018-2030 [Member]	Sep. 30, 2012 Foreign Tax Information [Member]	Sep. 30, 2012 Minimum State Tax Statute of Limitations [Member]	Sep. 30, 2012 Maximum State Tax Statute of Limitations [Member]	Sep. 30, 2012 Maximum [Member]
Unrecognized Tax Benefits		$ 0.9
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration			50.0	7.5	42.5
Deferred Other Tax Expense (Benefit)	$ 2.7
Other Information Pertaining to Income Taxes						one	four	six	ten