Intangible assets (Tables)

12 Months Ended

Dec. 31, 2019

Goodwill And Intangible Assets Disclosure [Abstract]

Summary of Intangible Assets

	Professional Services Agreements		Patents		Total
Cost
Balance as at January 1, 2018	$	215,844,537	$	532,598	$	216,377,135
Additions through asset acquisitions (note 4)		40,646,723		—		40,646,723
Balance as at December 31, 2018	$	256,491,260	$	532,598	$	257,023,858
Additions through asset acquisitions and adjustments    (note 4)		18,622,130		—	$	18,622,130
Balance as at December 31, 2019	$	275,113,390	$	532,598	$	275,645,988

	Professional Services Agreements		Patents		Total
Accumulated depreciation
Balance as at January 1, 2018	$	45,752,303	$	497,417	$	46,249,720
Amortization expense		31,387,429		2,446		31,389,875
Balance as at December 31, 2018	$	77,139,732	$	499,863	$	77,639,595
Amortization expense and adjustments (note 4)		34,895,944		2,256		34,898,200
Balance as at December 31, 2019	$	112,035,676	$	502,119	$	112,537,795

	Professional Services Agreements		Patents		Total
Net book value
December 31, 2019	$	163,077,714	$	30,479	$	163,108,193
December 31, 2018	$	179,351,528	$	32,735	$	179,384,263

Summary of Amortization Expense to be Incurred by Company Over Next Five Years

Based on the Company’s professional services agreements in place at December 31, 2019, the Company anticipates that the amortization expense to be incurred by the Company over the next five years is as follows:

	Amortization Expense
For professional services agreements as at December 31, 2019:
2020	$	37,438,739
2021		32,132,360
2022		25,411,084
2023		21,264,710
2024		19,339,571
	$	135,586,464