Taxes - Schedule of Income Tax Expense Reported (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
United States	$ (27,984)	$ (14,610)	$ (51,215)
Foreign	123,959	166,097	88,545
INCOME BEFORE INCOME TAXES	$ 95,975	$ 151,487	$ 37,330
Statutory rate	33.00%	37.00%	35.00%
Income tax expense expected	$ 31,672	$ 56,050	$ 13,066
Impact of foreign taxes	9,387	7,011	12,310
Foreign currency translation	11,527	10,336	(118)
Other local taxes	504	524	1,056
Stock-based compensation	430	324	2,001
Change in valuation allowance	3,429	(21,954)	52,269
Non-deductible third party royalty in Colombia	2,240	3,194	3,194
Other permanent differences	(1,904)	(6,614)	(14,740)
INCOME TAX EXPENSE (RECOVERY)	$ 57,285	$ 48,871	$ 69,038
Effective tax rate	60.00%	32.00%	185.00%
Current income tax expense
United States	$ 0	$ 0	$ 3,457
Foreign	17,058	43,903	20,865
Current income tax expense	17,058	43,903	24,322
Deferred income tax expense
Foreign	$ 40,227	$ 4,968	$ 44,716

Effective Income Tax Rate Reconciliation, Foreign Currency Transaction Adjustmets

No definition available.

Name:	gte_EffectiveIncomeTaxRateReconciliationForeignCurrencyTransactionAdjustmets
Namespace Prefix:	gte_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to third party royalty payments.

+ References

No definition available.