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Stock Options and Restricted Stock (Tables) | 12 Months Ended
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Dec. 31, 2012
Stock Options and Restricted Stock [Abstract] |
Stock options outstanding |
|  | Shares |  |  | Weighted- Average Exercise Price |  |  | Weighted- Average Remaining Contractual Life (in years) |
Outstanding at January 1, 2010 |  |  | 1,468,855 |  |  |  | 10.34 |  |  |  | 7.4 |
Granted |  |  | — |  |  |  | — |  |  |  | — |
Exercised |  |  | (153,157 | ) |  |  | 9.50 |  |  |  | — |
Canceled, forfeited, or expired |  |  | (45,000 | ) |  |  | — |  |  |  | — |
Outstanding at December 31, 2010 |  |  | 1,270,698 |  |  |  | 10.28 |  |  |  | 6.4 |
Exercisable at December 31, 2010 |  |  | 1,118,498 |  |  |  | 9.49 |  |  |  | 6.1 |
Outstanding at January 1, 2011 |  |  | 1,270,698 |  |  |  | 10.28 |  |  |  | 6.4 |
Granted |  |  | — |  |  |  | — |  |  |  | — |
Exercised |  |  | (338,350 | ) |  |  | 9.87 |  |  |  | — |
Canceled, forfeited, or expired |  |  | (13,000 | ) |  |  | — |  |  |  | — |
Outstanding at December 31, 2011 |  |  | 919,348 |  |  |  | 10.37 |  |  |  | 5.5 |
Exercisable at December 31, 2011 |  |  | 832,948 |  |  |  | 9.70 |  |  |  | 5.2 |
Outstanding at January 1, 2012 |  |  | 919,348 |  |  |  | 10.37 |  |  |  | 5.5 |
Granted |  |  | — |  |  |  | — |  |  |  | — |
Exercised |  |  | (86,800 | ) |  |  | 9.00 |  |  |  | — |
Canceled, forfeited, or expired |  |  | — |  |  |  | — |  |  |  | — |
Outstanding at December 31, 2012 |  |  | 832,548 |  |  |  | 10.51 |  |  |  | 4.6 |
Exercisable at December 31, 2012 |  |  | 779,948 |  |  |  | 10.08 |  |  |  | 4.4 |
Weighted-average grant date fair values of options granted |
|  | 2012 |  |  | 2011 |  |  | 2010 |
Cash received from option exercises |  | $ | 781,000 |  |  | $ | 3,339,000 |  |  | $ | 1,455,000 |
Total tax benefits realized for tax deductions from options exercised |  |  | 405,000 |  |  |  | 1,025,000 |  |  |  | 233,000 |
Total intrinsic value of options exercised |  |  | 1,468,000 |  |  |  | 4,240,000 |  |  |  | 1,238,000 |
Fair value of shares vested |  |  | 310,000 |  |  |  | 315,000 |  |  |  | 1,245,000 |
Aggregate intrinsic value of vested shares outstanding |  |  | 13,393,000 |  |  |  | 11,288,000 |  |  |  | 8,961,000 |
Restricted stock outstanding |
|  | Shares |  |  | Weighted-Average Grant-Date Fair Value per Share |
Nonvested balance at January 1, 2010 |  |  | — |  |  |  |  |
Granted |  |  | — |  |  |  |  |
Vested |  |  | — |  |  |  |  |
Forfeited |  |  | — |  |  |  |  |
Nonvested balance at December 31, 2010 |  |  | — |  |  |  |  |
Granted |  |  | — |  |  |  |  |
Vested |  |  | — |  |  |  |  |
Forfeited |  |  | — |  |  |  |  |
Nonvested balance at December 31, 2011 |  |  | — |  |  |  |  |
Granted |  |  | 8,000 |  |  |  | 27.47 |
Vested |  |  | — |  |  |  |  |
Forfeited |  |  | — |  |  |  |  |
Nonvested balance at December 31, 2012 |  |  | 8,000 |  |  |  | 27.47 |
|  | Shares |  |  | Weighted-Average Grant-Date Fair Value per Share |
Nonvested balance at January 1, 2010 |  |  | 5,844 |  |  |  | 15.39 |
Granted |  |  | 12,246 |  |  |  | 17.76 |
Vested |  |  | (6,260 | ) |  |  | 15.56 |
Forfeited |  |  | — |  |  |  | — |
Nonvested balance at December 31, 2010 |  |  | 11,830 |  |  |  | 17.75 |
Granted |  |  | 9,513 |  |  |  | 22.06 |
Vested |  |  | (11,830 | ) |  |  | 17.75 |
Forfeited |  |  | — |  |  |  | — |
Nonvested balance at December 31, 2011 |  |  | 9,513 |  |  |  | 22.06 |
Granted |  |  | 7,833 |  |  |  | 26.79 |
Vested |  |  | (9,513 | ) |  |  | 22.06 |
Forfeited |  |  | — |  |  |  | — |
Nonvested balance at December 31, 2012 |  |  | 7,833 |  |  |  | 26.79 |
|  | Shares |  |  | Weighted-Average Grant-Date Fair Value per Share |
Nonvested balance at December 31, 2011 |  |  | — |  |  |  | — |
Granted |  |  | 2,331 |  |  |  | 26.79 |
Vested |  |  | — |  |  |  | — |
Forfeited |  |  | — |  |  |  | — |
Nonvested balance at December 31, 2012 |  |  | 2,331 |  |  |  | 26.79 |

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- Definition Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the weighted-average grant-date fair value of equity options or other equity instruments granted during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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