Debt (Tables)

3 Months Ended

Mar. 31, 2018

Debt [Abstract]

Schedule of Debt

			Carrying amount
			March 31,		December 31,
				2018		2017
Short-term debt			$	5,861	$	7,018
Long-term debt:
	Term Loans (previously referred to as Delayed draw term loans):
		Denominated in Canadian dollars, secured, bearing interest at a weighted
		average rate of 4.014%, due in monthly installments of interest only and
		quarterly installments of principal, maturing in October 2021		178,335		185,143
		Denominated in United States dollars, secured, bearing interest at a weighted
		average rate of 4.064%, due in weekly installments of interest only and
		quarterly installments of principal, maturing in October 2021		117,691		144,544
		Less: unamortized debt issue costs		(3,514)		(4,134)
	Senior unsecured notes:
		Bearing interest at 5.375% due in semi-annual installments, with the full
		amount of principal due in January 2025		500,000		500,000
		Less: unamortized debt issue costs		(12,218)		(12,661)
Total Long-term debt				780,294		812,892
Total debt			$	786,155	$	819,910
Long-term debt:
Current portion			$	9,264	$	16,907
Non-current portion				771,030		795,985
Total Long-term debt			$	780,294	$	812,892