Consolidated Statements of Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Loss on disposal of discontinued operations, tax	$ 0	$ 350	$ 0	$ 350

Amount of tax expense or benefit on gain (loss), not previously recognized, resulting from the sale of a business component.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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