Long-term debt (Tables)

12 Months Ended

Dec. 31, 2018

Financial Instruments [Abstract]

Schedule of long-term debt

As at	Dec 31 2018			Dec 31 2017
Unsecured notes
(i) 3.25% due December 15, 2019	$	349,026		$	348,060
(ii) 5.25% due March 1, 2022	248,480			248,072
(iii) 4.25% due December 1, 2024	297,232			296,873
(iv) 5.65% due December 1, 2044	295,238			295,158
	1,189,976			1,188,163
Egypt limited recourse debt facilities	101,226			241,190
Other limited recourse debt facilities
(i) LIBOR+0.75% to LIBOR+2.5% due through 2019 to 2021	5,483			72,918
(ii) 5.58% due through June 30, 2031	77,709			—
(iii) 5.35% due through September 30, 2033	83,892			—
	167,084			72,918
Total long-term debt1	1,458,286			1,502,271
Less current maturities1	(383,793		)	(55,905		)
	$	1,074,493		$	1,446,366

¹ Long-term debt and current maturities are presented net of discounts and deferred financing fees of $17.6 million as at December 31, 2018 (2017 - $17.8 million).

Schedule of minimum principal payments for long-term debt

The minimum principal payments for long-term debt in aggregate and for each of the five succeeding years are as follows:

	Egypt limited recourse debt facilities		Other limited recourse debt facilities		Unsecured notes		Total
2019	$	27,640	$	8,352	$	350,000	$	385,992
2020	29,525		10,452		—		39,977
2021	31,552		9,129		—		40,681
2022	16,606		10,213		250,000		276,819
2023	—		10,778		—		10,778
Thereafter	—		121,604		600,000		721,604
	$	105,323	$	170,528	$	1,200,000	$	1,475,851