Partnership Income, Expenses and Cash Distributions - Additional Information (Details)	Jun. 30, 2018
Tier 2 [Member]
Penalty on Outstanding Contingent Interest	0.90%
Limited Partner [Member] | Tier 1 [Member]
Percent of Regular Distributions	99.00%
Limited Partner [Member] | Tier 2 [Member]
Special Distribution	75.00%
Limited Partner [Member] | Tier 3 [Member]
Special Distribution	100.00%
General Partner [Member] | Tier 1 [Member]
Percent of Regular Distributions	1.00%
General Partner [Member] | Tier 2 [Member]
Special Distribution	25.00%