Share Capital (Tables)

12 Months Ended

Dec. 31, 2019

Equity [Abstract]

Schedule of Common Stock

	Shares of Common Stock		Exchangeable Shares of Gran Tierra Exchangeco Inc.		Exchangeable Shares of Gran Tierra Goldstrike Inc.
Balance, December 31, 2016	390,807,194		4,812,592		3,387,302
Shares repurchased and canceled	(7,704,381	)	—		—
Exchange of exchangeable shares	2,088,229		(389,816	)	(1,698,413	)
Balance, December 31, 2017	385,191,042		4,422,776		1,688,889
Options exercised	549,189		—		—
Shares repurchased and canceled	(4,772,869	)	—
Exchange of exchangeable shares	6,111,665		(4,422,776	)	(1,688,889	)
Balance, December 31, 2018	387,079,027		—		—
Shares repurchased and canceled	(20,097,471	)	—		—
Balance, December 31, 2019	366,981,556		—		—

Schedule of Information About PSU, DSU, RSU and Stock Option Activity

The following table provides information about PSU, DSU and stock option activity for the year ended December 31, 2019:

	PSUs		DSUs	Stock Options
	Number of Outstanding Share Units		Number of Outstanding Share Units	Number of Outstanding Stock Options		Weighted Average Exercise Price /Stock Option ($)
Balance, December 31, 2018	9,004,661		684,893	9,034,412		$	3.18
Granted	6,355,214		567,101	2,943,990		2.04
Exercised	(2,725,877	)	—	—		—
Forfeited	(1,262,631	)	—	(1,213,170	)	3.61
Expired	—		—	(152,360	)	5.27
Balance, December 31, 2019	11,371,367		1,251,994	10,612,872		$	2.78
Vested and exercisable, at December 31, 2019				6,469,699		$	3.14
Vested, or expected to vest, at December 31, 2019 through the life of the options				10,445,530		$	2.79

Schedule of Assumptions Using the Black-Scholes Option Pricing Model

The fair value of each stock option award is estimated on the date of grant using the Black-Scholes option pricing model based on assumptions noted in the following table:

	Year Ended December 31,
	2019		2018		2017
Dividend yield (per share)	Nil		Nil		Nil
Volatility	48% to 54%		51% to 55%		51% to 53%
Weighted average volatility	51	%	54	%	52	%
Risk-free interest rate	1.49% to 2.54%		2.18% to 3.00%		1.75% to 2.10%
Expected term	4-5 years		4-5 years		4-5 years

Schedule of Weighted Average Number of Shares

Weighted Average Shares Outstanding

	Year Ended December 31,
	2019		2018		2017
Weighted Average number of common and exchangeable shares outstanding	376,495,306		390,930,453		396,683,593
Shares issuable pursuant to stock options	87,204		4,207,542		—
Shares assumed to be purchased from proceeds of stock options	(74,698	)	(3,832,516	)	—
Shares issuable on conversion of Convertible Notes	—		35,814,393		—
Weighted average number of diluted common and exchange shares outstanding	376,507,812		427,119,872		396,683,593