| Three Months Ended September 30, | Nine Months Ended September 30, | ||||||||||||||||
| 2013 | 2012 | 2013 | 2012 | ||||||||||||||
| Earnings | |||||||||||||||||
| Pre-tax net income | $ | 11,821 | $ | 5,226 | $ | 20,716 | $ | 15,554 | |||||||||
| Add: | |||||||||||||||||
| Fixed charges | 9,747 | 9,092 | 29,907 | 24,703 | |||||||||||||
| Earnings, as adjusted | $ | 21,568 | $ | 14,318 | $ | 50,623 | $ | 40,257 | |||||||||
| Fixed charges | |||||||||||||||||
| Interest expensed and capitalized | $ | 9,067 | $ | 8,508 | $ | 28,024 | $ | 22,915 | |||||||||
| Amortized premiums, discounts and capitalized expenses related to indebtedness | 672 | 577 | 1,860 | 1,766 | |||||||||||||
| Estimate of interest within rental expense | 8 | 7 | 23 | 22 | |||||||||||||
| Fixed charges, as adjusted | 9,747 | 9,092 | 29,907 | 24,703 | |||||||||||||
Preferred stock dividends (1) | 2,579 | — | 5,406 | — | |||||||||||||
| Combined fixed charges and preferred stock dividends | $ | 12,326 | $ | 9,092 | $ | 35,313 | $ | 24,703 | |||||||||
| Ratio of earnings to combined fixed charges and preferred stock dividends | 1.75 | x | 1.57 | x | 1.43 | x | 1.63 | x | |||||||||
