CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Oil and natural gas properties, unproved property costs	$ 1,084,737	$ 1,063,884
Other property and equipment accumulated depreciation and amortization	$ 0	$ 14,433
Series B Cumulative Convertible Preferred Units
Partners' equity, preferred units, outstanding (in shares)	14,711	14,711
Common Units
Partners' equity - units, outstanding (in shares)	109,377	108,363
Subordinated Units
Partners' equity - units, outstanding (in shares)	96,329	96,329

Capitalized costs of unproved properties incurred for any combination mineral interests acquisitions and other costs not previously disclosed within this table.

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