Income Taxes Pretax Income (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income (loss) before income taxes	$ 158,057	$ 158,211	$ 150,634
U.S. [Member]
Income (loss) before income taxes	138,102	140,511	135,927
Outside the U.S. [Member]
Income (loss) before income taxes	$ 19,955	$ 17,700	$ 14,707

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 10

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration