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Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Income Taxes |  |  |
Income tax expense differences from the amount computed by applying the U.S. Federal income tax rate to income before income taxes (as a percent) | 35.00% | 35.00% | 35.00%
Reasons for the difference of income tax expense |  |  |
Computed expected tax expense | $ 66,941 | $ 70,355 | $ 77,293
Change in taxes resulting from: |  |  |
Tax-exempt interest income | (3,682) | (2,813) | (1,937)
State tax, net of federal income taxes and tax credit | 3,302 | 2,594 | 5,722
Tax refunds |  | (2,143) |
Litigation expense |  | 5,375 |
Other investment income | (3,083) | (3,172) | (3,526)
Other | 600 | 761 | 436
Total income taxes | $ 64,078 | $ 70,957 | $ 77,988

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- Definition The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=6889476&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 47 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 + Details
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