Impairment Charges - Summary of Pre-tax Impairment Charges Included in Impairment Expense (Details) - USD ($) $ in Thousands	3 Months Ended					12 Months Ended
	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held-for-use	$ 702	$ 5,546	$ 28,661	$ 27,244	$ 4,360
Goodwill, impairment loss	19,900
Impairment expense			28,661			$ 26,148	$ 28,661	$ 31,604
Canada
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held-for-use	702	0	28,661	27,244	4,360
Goodwill, impairment loss	19,900
Impairment expense			28,661			20,602		31,604
Australia
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held-for-use	0	5,546	0	0	0
Goodwill, impairment loss	0
Impairment expense			0			5,546		0
U.S.
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held-for-use	0	$ 0	0	$ 0	$ 0
Goodwill, impairment loss	$ 0
Impairment expense			$ 0			$ 0		$ 0