Income Taxes - Summary of Tax Credit Carryforwards (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards, Tax Effected	$ 74,503	$ 80,182
Interest limitation carryforwards, Tax Effected	15,537	5,820
Canadian pool of SR&ED, Tax Effected	87,315	$ 87,253
Foreign
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards, Gross Amount	49,143
Tax credit carryforwards, Tax Effected	49,143
Tax credit carryforwards, Valuation Allowance	(49,143)
Net operating losses, Gross Amount	910,097
Net operating losses, Tax Effected	201,504
Net operating losses, Valuation Allowance	(3,180)
Canadian pool of SR&ED, Gross Amount	407,587
Canadian pool of SR&ED, Tax Effected	87,315
Canadian pool of SR&ED, Valuation Allowance	0
State
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards, Gross Amount	24,260
Tax credit carryforwards, Tax Effected	24,260
Tax credit carryforwards, Valuation Allowance	(24,018)
Net operating losses, Gross Amount	71,521
Net operating losses, Tax Effected	3,249
Net operating losses, Valuation Allowance	(2,782)
Federal
Operating Loss Carryforwards [Line Items]
Net operating losses, Gross Amount	19,329
Net operating losses, Tax Effected	4,059
Net operating losses, Valuation Allowance	0
Interest limitation carryforwards, Gross Amount	70,624
Interest limitation carryforwards, Tax Effected	15,537
Interest limitation carryforwards, Valuation Allowance	$ (15,537)