Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands |
Jun. 30, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Accumulated amortization of debt financing costs | $ 2,409 | $ 2,580 |
| Class A common stock, par value (in dollars per share) | $ 0.01 | $ 0.01 |
| Class A common stock, shares authorized | 500,000,000 | 500,000,000 |
| Class A common stock, shares outstanding | 98,096,323 | 97,860,048 |
| Treasury stock, shares | 178,346 | 157,812 |