Quarterly report pursuant to Section 13 or 15(d)

Condensed Consolidated Balance Sheets (Parenthetical)

v3.20.1
Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2020
Dec. 31, 2019
Property, plant and equipment, accumulated depreciation $ 14,544 $ 11,313
Less: accumulated depletion $ 318 $ 260
Certificates of proprietary interest, par value (in dollars per share) $ 100 $ 100
Certificates of proprietary interest, outstanding (in shares) 0 0
Sub-share certificates of proprietary interest, par value (in dollars per share) $ 0.0333 $ 0.0333
Sub-share certificates of proprietary interest, outstanding (in shares) 7,756,156 7,756,156
1/16th nonparticipating perpetual royalty interest    
Nonparticipating perpetual royalty interest rate 6.25% 6.25%
1/128th nonparticipating perpetual royalty interest    
Nonparticipating perpetual royalty interest rate 0.78125% 0.78125%