| Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] |
| | | For the three months ended September 30: | | | For the nine months ended September 30: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Net income | | $ | 12,868 | | | $ | 4,850 | | | $ | 37,661 | | | $ | 16,774 | | | Less: distributed earnings allocated to non-vested stock | | | (8 | ) | | | (15 | ) | | | (32 | ) | | | (52 | ) | | Less: undistributed earnings allocated to non-vested restricted stock | | | (35 | ) | | | (12 | ) | | | (131 | ) | | | (57 | ) | Numerator for basic earnings per share | | $ | 12,825 | | | $ | 4,823 | | | $ | 37,498 | | | $ | 16,665 | | Effect of dilutive securities: | | | | | | | | | | | | | | | | | | Add: undistributed earnings allocated to non-vested restricted stock | | | 35 | | | | 12 | | | | 131 | | | | 57 | | | Less: undistributed earnings reallocated to non-vested restricted stock | | | (35 | ) | | | (12 | ) | | | (131 | ) | | | (61 | ) | Numerator for diluted earnings per share | | $ | 12,825 | | | $ | 4,823 | | | $ | 37,498 | | | $ | 16,661 | | | | | | | | | | | | | | | | | | | | Weighted average shares outstanding – basic | | | 43,570,734 | | | | 43,460,449 | | | | 43,524,729 | | | | 43,418,243 | | Effect of dilutive securities: | | | | | | | | | | | | | | | | | | Stock options and other awards | | | 2,263 | | | | 837 | | | | 4,694 | | | | 6,180 | | Weighted average shares outstanding – diluted | | | 43,572,997 | | | | 43,461,286 | | | | 43,529,423 | | | | 43,424,423 | | | | | | | | | | | | | | | | | | | | | | | $ | 0.29 | | | $ | 0.11 | | | $ | 0.86 | | | $ | 0.38 | | Diluted earnings per share | | $ | 0.29 | | | $ | 0.11 | | | $ | 0.86 | | | $ | 0.38 | | |