Other Long-Term Liabilities (Tables)

12 Months Ended

Dec. 31, 2018

Other Liabilities Disclosure [Abstract]

Schedule of Other Long-Term Liabilities and Deferred Credits

Other long-term liabilities and deferred credits on the balance sheet consisted of:

	December 31,
	2018		2017
	(thousands of dollars)
Royalties payable (1)	$	500	$	500
	$	500	$	500

_________________

(1) Royalties payable were derived during prior years of production. Liabilities do not accrue interest or have a stated maturity date.