Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands |
Sep. 30, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Allowance for doubtful accounts receivable | $ 4,174 | $ 3,448 |
| Deferred debt issuance costs, accumulated amortization | $ 2,897 | $ 2,362 |
| Trust shares, par value | ||
| Trust shares, authorized | 500,000,000 | 500,000,000 |
| Trust shares, issued | 54,300,000 | 54,300,000 |
| Trust shares, outstanding | 54,300,000 | 54,300,000 |