Summary of Significant Accounting Policies (Assets and Liabilities Measured on Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
SARs liability	$ 609	$ 2,289
Derivative liability - crude oil swaps	4,806
SARs liability		193
Liabilities	5,415	2,482
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
SARs liability	609	2,289
Derivative liability - crude oil swaps	4,806
SARs liability		193
Liabilities	$ 5,415	$ 2,482