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Employee Benefit Plans (Details Textual) (USD $) | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Employee Benefit Plans |  |  |
Minimum age required to be considered eligible for plan | 21 |  |
Period of Employment Required to be Eligible for Plan | 3 |  |
Minimum number of quarters required to be eligible for employer discretionary contribution | 1 |  |
Minimum number of hours required to be considered eligible for employer discretionary contribution | 501 |  |
Number of officers in employment contract | 26 |  |
401(k) and Profit Sharing Plans |  |  |
401(k) and Profit Sharing Plans |  |  |
Percent rate for non-elective safe harbor contribution as component of profit sharing plan | 3.00% |  |
Profit Sharing Plan Expense | $ 5,862,000 | $ 3,974,000 | $ 2,043,000
Maximum percentage of annual compensation allowable for contribution by eligible employees | 60.00% |  |
Percentage of amount out of first specific percent of employee's contribution matched under plan | 50.00% |  |
Percentage of employee's contribution required to determine the matched amount under the plan | 6.00% |  |
Company's contribution to the plan | 1,935,000 | 1,751,000 | 1,644,000
Deferred Compensation Plans |  |  |
Deferred Compensation Plans |  |  |
Percentage of salary for deferral of cash payments | 50.00% |  |
Percentage of bonuses and directors fees for deferral of cash payments | 100.00% |  |
Total amount deferred | 376,000 | 278,000 | 362,000
Liability related to obligations of deferred compensation plans | 5,042,000 | 1,255,000 |
Employee Benefit Plans |  |  |
Credit earning rate as a percentage of return on equity | 50.00% |  |
Total earnings for the plan | 515,000 | 231,000 | 54,000
Supplemental Employee Retirement Plan (SERP) |  |  |
Employee Benefit Plans |  |  |
Company's contribution to the plan | 76,000 | 47,000 | 21,000
Credit earning rate as a percentage of return on equity | 50.00% |  |
Total earnings for the plan | $ 48,000 | $ 37,000 | $ 9,000

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