Significant Accounting Policies (Details) |
3 Months Ended | 12 Months Ended |
|---|---|---|
Mar. 31, 2019 |
Dec. 31, 2018 |
|
| Significant Accounting Policies [Line Items] | ||
| Number of days to determine non-performance of loan | 90 days | 90 days |
| Long-Term Incentive Plan Units [Member] | Director [Member] | ||
| Significant Accounting Policies [Line Items] | ||
| Vesting period | 1 year | 1 year |
| Minimum | Long-Term Incentive Plan Units [Member] | Dedicated or partially dedicated personnel [Member] | ||
| Significant Accounting Policies [Line Items] | ||
| Vesting period | 1 year | |
| Maximum | Long-Term Incentive Plan Units [Member] | Dedicated or partially dedicated personnel [Member] | ||
| Significant Accounting Policies [Line Items] | ||
| Vesting period | 2 years |