Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		3 Months Ended				9 Months Ended				12 Months Ended
		Sep. 30, 2019		Sep. 30, 2018		Sep. 30, 2019		Sep. 30, 2018		Dec. 31, 2018
Operating activities:
Net income (loss)		$ 1,070		$ (1,720)		$ (2,841)		$ (4,501)
Adjustments to reconcile net loss to net cash provided by operating activities:
Share-based compensation						298		340
Foreign currency loss						1,776		20,748
Interest on Series A Preferred Shares paid in common shares						3,684
Loss on derivative contracts		(403)		1,290		30		5,156
Cash settlement on derivative contracts								(3,710)
Amortization on loan financing costs						31		31
Deferred income tax expense						4,396		5,577
Exploration, abandonment and impairment		488		162		6,267		393
Depreciation, depletion and amortization		3,021		2,938		10,179		10,673
Accretion of asset retirement obligations		56		35		157		124		$ 174
Changes in operating assets and liabilities:
Accounts receivable						172		(14,920)
Prepaid expenses and other assets						(6,567)		(6,831)
Accounts payable and accrued liabilities						8,122		12,136
Net cash provided by operating activities						25,704		25,216
Investing activities:
Additions to oil and natural gas properties						(24,847)		(17,708)
Additions to equipment and other properties						(341)		(3,254)
Net cash used in investing activities						(25,188)		(20,962)
Financing activities:
Tax withholding on restricted share units						(97)		(15)
Note receivable - related party						1,000
Loan proceeds						20,605		10,000
Loan repayment						(16,550)		(12,425)
Net cash provided by (used in) financing activities						4,958		(2,440)
Effect of exchange rate on cash flows, cash equivalents, and restricted cash						(914)		(8,535)
Net increase (decrease) in cash, cash equivalents and restricted cash						4,560		(6,721)
Cash, cash equivalents and restricted cash, beginning of period	[1]					10,032		20,432		20,432
Cash, cash equivalents and restricted cash, end of period		$ 14,592	[2]	$ 13,711	[2]	14,592	[2]	13,711	[2]	$ 10,032	[1]
Supplemental disclosures:
Cash paid for interest						3,387		7,333
Cash paid for taxes						$ 2,988		$ 2,847

[1] The beginning of period balance at December 31, 2018 includes cash and cash equivalents of $9.9 million and restricted cash of $0.1 million in other assets. The beginning of period balance at December 31, 2017 includes cash and cash equivalents of $18.9 million and restricted cash of $1.5 million in other assets

[2] The end of period balance at September 30, 2019 includes cash and cash equivalents of $14.5 million and restricted cash of $0.1 million in other assets. The end of period balance at September 30, 2018 includes cash and cash equivalents of $13.6 million and restricted cash of $0.1 million in other assets.