Debt - Additional Information - Debt Extinguishment (Details) $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Dec. 31, 2017
USD ($)
Loan
|
Sep. 30, 2017
USD ($)
|
Jun. 30, 2017
USD ($)
|
Mar. 31, 2017
USD ($)
|
Dec. 31, 2016
USD ($)
Loan
|
Sep. 30, 2016
USD ($)
|
Jun. 30, 2016
USD ($)
|
Mar. 31, 2016
USD ($)
|
Dec. 31, 2017
USD ($)
Loan
|
Dec. 31, 2016
USD ($)
Loan
|
Dec. 31, 2015
USD ($)
|
|
| Debt Instrument [Line Items] | |||||||||||
| Loss (gain) on debt extinguishment | $ 1,190 | $ (1,792) | $ (7) | $ 30 | $ 77 | $ 8,016 | $ (14,777) | $ 5,079 | $ (579) | $ (1,605) | $ 2,375 |
| Master Trust Notes | Subsidiaries | |||||||||||
| Debt Instrument [Line Items] | |||||||||||
| Weighted average interest rate | 6.01% | 6.01% | |||||||||
| Number of notes paid off | Loan | 7 | 7 | |||||||||
| Series 2014-1 Class A1 | Master Trust Notes | |||||||||||
| Debt Instrument [Line Items] | |||||||||||
| Number of notes paid off | Loan | 1 | 1 | |||||||||
| Master Trust Notes | |||||||||||
| Debt Instrument [Line Items] | |||||||||||
| Amount of extinguishment of debt | $ 238,500 | ||||||||||
| Weighted average interest rate | 5.50% | 5.50% | |||||||||
| Loss (gain) on debt extinguishment | $ (1,600) | $ (200) | |||||||||
| Master Trust Notes | Subsidiaries | |||||||||||
| Debt Instrument [Line Items] | |||||||||||
| Amount of extinguishment of debt | $ 883,000 | ||||||||||