Gran Tierra Energy (GTE) 10-Q 4 Nov 15 2015 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 30, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	GRAN TIERRA ENERGY INC.
Entity Central Index Key	1,273,441
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		274,499,439
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Retained Earnings - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
REVENUE AND OTHER INCOME
Oil and natural gas sales	$ 75,653	$ 161,517	$ 221,234	$ 460,510
Interest income	266	772	1,069	2,160
Total revenue and other income	75,919	162,289	222,303	462,670
EXPENSES
Operating	33,751	33,949	89,318	81,161
Depletion, depreciation, accretion and impairment	204,993	53,936	360,620	140,137
General and administrative	7,863	13,350	25,455	40,145
Severance	461	0	6,827	0
Equity tax	0	0	3,769	0
Foreign exchange gain	(12,923)	(12,438)	(21,492)	(6,604)
Financial instruments loss (gain)	2,670	2,790	1,262	(2,223)
Total expenses	236,815	91,587	465,759	252,616
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(160,896)	70,702	(243,456)	210,054
INCOME TAX (EXPENSE) RECOVERY
Current	(3,523)	(24,246)	(11,632)	(83,183)
Deferred	62,542	(2,272)	69,781	(1,431)
Income tax expense	59,019	(26,518)	58,149	(84,614)
(LOSS) INCOME FROM CONTINUING OPERATIONS	(101,877)	44,184	(185,307)	125,440
Loss from discontinued operations, net of income taxes	0	0	0	(26,990)
NET INCOME (LOSS) AND COMPREHENSIVE INCOME (LOSS)	(101,877)	44,184	(185,307)	98,450
RETAINED EARNINGS, BEGINNING OF PERIOD	156,192	465,227	239,622	410,961
RETAINED EARNINGS, END OF PERIOD	$ 54,315	$ 509,411	$ 54,315	$ 509,411
Basic
(LOSS) INCOME FROM CONTINUING OPERATIONS (in dollars per share)	$ (0.36)	$ 0.15	$ (0.65)	$ 0.44
LOSS FROM DISCONTINUED OPERATIONS, NET OF INCOME TAXES (in dollars per share)	0	0	0	(0.09)
NET INCOME (LOSS) (in dollars per share)	(0.36)	0.15	(0.65)	0.35
Diluted
(LOSS) INCOME FROM CONTINUING OPERATIONS (in dollars per share)	(0.36)	0.15	(0.65)	0.44
LOSS FROM DISCONTINUED OPERATIONS, NET OF INCOME TAXES (in dollars per share)	0	0	0	(0.09)
NET INCOME (LOSS) (in dollars per share)	$ (0.36)	$ 0.15	$ (0.65)	$ 0.35
WEIGHTED AVERAGE SHARES OUTSTANDING - BASIC	285,592,382	285,576,898	286,057,952	284,203,679
WEIGHTED AVERAGE SHARES OUTSTANDING - DILUTED	285,592,382	288,059,601	286,057,952	287,569,347

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current Assets
Cash and cash equivalents	$ 186,978	$ 331,848
Restricted cash	303	1,836
Accounts receivable	21,426	83,227
Marketable securities	7,016	7,586
Inventory	19,073	17,298
Taxes receivable	27,507	15,843
Prepaids	3,462	6,000
Deferred tax assets	583	1,552
Total Current Assets	266,348	465,190
Oil and Gas Properties
Proved	546,069	801,075
Unproved	326,717	316,856
Total Oil and Gas Properties	872,786	1,117,931
Other capital assets	9,478	11,013
Total Property, Plant and Equipment	882,264	1,128,944
Other Long-Term Assets
Restricted cash	3,272	2,037
Deferred tax assets	483	601
Taxes receivable	9,250	9,684
Other long-term assets	6,670	5,013
Goodwill	102,581	102,581
Total Other Long-Term Assets	122,256	119,916
Total Assets	1,270,868	1,714,050
Current Liabilities
Accounts payable	25,984	112,401
Accrued liabilities	44,123	75,430
Foreign currency derivative	0	3,057
Taxes payable	750	25,412
Deferred tax liabilities	21	1,040
Asset retirement obligation	4,686	8,026
Total Current Liabilities	75,564	225,366
Long-Term Liabilities
Deferred tax liabilities	74,596	175,324
Asset retirement obligation	27,167	27,786
Other long-term liabilities	6,523	8,889
Total Long-Term Liabilities	$ 108,286	$ 211,999
Contingencies
Shareholders’ Equity
Common Stock (274,814,539 and 276,072,351 shares of Common Stock and 8,616,666 and 10,119,745 exchangeable shares, par value $0.001 per share, issued and outstanding as at September 30, 2015, and December 31, 2014, respectively)	$ 10,187	$ 10,190
Additional paid in capital	1,022,516	1,026,873
Retained earnings	54,315	239,622
Total Shareholders’ Equity	1,087,018	1,276,685
Total Liabilities and Shareholders’ Equity	$ 1,270,868	$ 1,714,050

Condensed Consolidated Balance4

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common shares, par value (in dollars per share)	$ 0.001	$ 0.001
Common shares, issued	274,814,539	276,072,351
Common shares, outstanding	274,814,539	276,072,351
Exchangeable shares, issued	8,616,666	10,119,745
Exchangeable shares, outstanding	8,616,666	10,119,745

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Operating Activities
Net income (loss)	$ (185,307)	$ 98,450
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Loss from discontinued operations, net of income taxes	0	26,990
Depletion, depreciation, accretion and impairment	360,620	140,137
Deferred tax (recovery) expense	(69,781)	1,431
Non-cash stock-based compensation	1,511	4,341
Unrealized foreign exchange gain	(13,093)	(6,924)
Financial instruments loss (gain)	1,262	(2,223)
Equity tax	0	(3,283)
Cash settlement of foreign currency derivatives	(3,749)	4,662
Cash settlement of asset retirement obligation	(4,768)	(211)
Net change in assets and liabilities from operating activities of continuing operations
Accounts receivable and other long-term assets	52,133	(61,224)
Inventory	1,599	(1,688)
Prepaids	2,538	2,565
Accounts payable and accrued and other long-term liabilities	(36,935)	(981)
Taxes receivable and payable	(47,483)	(55,084)
Net cash provided by operating activities of continuing operations	58,547	146,958
Net cash used in operating activities of discontinued operations	0	(4,792)
Net cash provided by operating activities	58,547	142,166
Balance, September 30, 2015	31,853
Investing Activities
Decrease in restricted cash	298	877
Additions to property, plant and equipment	(116,353)	(268,859)
Changes in non-cash investing working capital	(75,152)	18,225
Net cash used in investing activities of continuing operations	(191,207)	(249,757)
Proceeds from sale of Argentina business unit, net of cash sold and transaction costs	0	42,755
Net cash used in investing activities of discontinued operations	0	(12,384)
Net cash used in investing activities	(191,207)	(219,386)
Financing Activities
Repurchase of shares of Common Stock	(6,616)	0
Proceeds from issuance of shares of Common Stock	602	11,177
Net cash (used in) provided by financing activities	(6,014)	11,177
Foreign exchange loss on cash and cash equivalents	(6,196)	(2,327)
Net decrease in cash and cash equivalents	(144,870)	(68,370)
Cash and cash equivalents, beginning of period	331,848	428,800
Cash and cash equivalents, end of period	186,978	360,430
Non-cash investing activities:
Net liabilities related to property, plant and equipment, end of period	$ 34,023	$ 72,410

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Share Capital [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]
Beginning balance at Dec. 31, 2013		$ 10,187	$ 1,008,760	$ 410,961
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issue of shares of Common Stock		3
Repurchase of shares of Common Stock		0	0
Exercise of stock options			11,137
Stock-based compensation			6,976
Net loss				(171,339)
Ending balance at Dec. 31, 2014	$ 1,276,685	10,190	1,026,873	239,622
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issue of shares of Common Stock		0
Repurchase of shares of Common Stock		(3)	(6,613)
Exercise of stock options			602
Stock-based compensation			1,654
Net loss	(185,307)			(185,307)
Ending balance at Sep. 30, 2015	$ 1,087,018	$ 10,187	$ 1,022,516	$ 54,315

Description of Business

Description of Business	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business Gran Tierra Energy Inc., a Nevada corporation (the “Company” or “Gran Tierra”), is a publicly traded oil and gas company engaged in the acquisition, exploration, development and production of oil and natural gas properties. The Company’s principal business activities are in Colombia, Peru and Brazil.

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies These interim unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”). The information furnished herein reflects all normal recurring adjustments that are, in the opinion of management, necessary for the fair presentation of results for the interim periods. The note disclosure requirements of annual consolidated financial statements provide additional disclosures to that required for interim unaudited condensed consolidated financial statements. Accordingly, these interim unaudited condensed consolidated financial statements should be read in conjunction with the Company’s consolidated financial statements as at and for the year ended December 31, 2014 , included in the Company’s 2014 Annual Report on Form 10-K, filed with the Securities and Exchange Commission (“SEC”) on March 2, 2015 . The Company’s significant accounting policies are described in Note 2 of the consolidated financial statements which are included in the Company’s 2014 Annual Report on Form 10-K and are the same policies followed in these interim unaudited condensed consolidated financial statements. The Company has evaluated all subsequent events through to the date these interim unaudited condensed consolidated financial statements were issued. Recently Issued Accounting Pronouncements Simplifying the Measurement of Inventory In July 2015, the FASB issued ASU 2015-11, “ Simplifying the Measurement of Inventory ". The ASU provides guidance for the subsequent measurement of inventory and requires that inventory that is measured using average cost be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The ASU will be effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. The implementation of this update is not expected to materially impact the Company’s consolidated financial position, results of operations or cash flows or disclosure. Revenue from Contracts with Customers In August 2015, the FASB issued ASU 2015-14, “Revenue from Contracts with Customers - Deferral of the Effective Date". The ASU defers the effective date of the new revenue recognition model by one year. As a result, the guidance will be effective for fiscal years, and interim periods within those years, beginning after December 15, 2017. The Company is currently assessing the impact the new revenue recognition model will have on its consolidated financial position, results of operations, cash flows, and disclosure.

Discontinued Operations

Discontinued Operations	9 Months Ended
	Sep. 30, 2015
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Discontinued Operations On June 25, 2014 , the Company, through several of its indirect subsidiaries, sold its Argentina business unit to Madalena Energy Inc. ("Madalena") for aggregate consideration of $69.3 million , comprising $55.4 million in cash and $13.9 million in Madalena shares. Accordingly, the results of the Company’s Argentina business unit are classified as “Loss from discontinued operations, net of income taxes” on the consolidated statements of operations for the nine months ended September 30, 2014 . Additionally, cash flows of the Company’s Argentina business unit are presented separately in the interim unaudited condensed consolidated statement of cash flows for the nine months ended September 30, 2014 , as cash provided by or used in operating and investing activities of discontinued operations. Revenue and other income and loss from discontinued operations, net of income taxes, for the nine months ended September 30, 2014 , were as follows: (Thousands of U.S. Dollars) Nine Months Ended September 30, 2014 Revenue and other income $ 31,985 Loss from operations of discontinued operations before income taxes $ (6,252 ) Income tax expense (1,458 ) Loss from operations of discontinued operations (7,710 ) Loss on sale before income taxes (18,235 ) Income tax expense (1,045 ) Loss on sale (19,280 ) Loss from discontinued operations, net of income taxes $ (26,990 )

Segment and Geographic Reportin

Segment and Geographic Reporting	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Segment and Geographic Reporting	Segment and Geographic Reporting The Company is primarily engaged in the exploration and production of oil and natural gas. The Company’s reportable segments are Colombia, Peru and Brazil based on geographic organization. Prior to classifying the Company’s Argentina business unit as discontinued operations, Argentina was a reportable segment. The All Other category represents the Company’s corporate activities. The amounts disclosed in the tables below exclude the results of the Argentina business unit. Certain subsidiaries which were previously included in the All Other category were sold as part of the Argentina business unit, and therefore amounts disclosed in the All Other category have been reclassified to exclude amounts reported in loss from discontinued operations. The Company evaluates reportable segment performance based on income or loss from continuing operations before income taxes. The following tables present information on the Company’s reportable segments and other activities: Three Months Ended September 30, 2015 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Oil and natural gas sales $ 73,557 $ — $ 2,096 $ — $ 75,653 Interest income 61 — — 205 266 Depletion, depreciation, accretion and impairment 181,981 3,208 19,396 408 204,993 Loss from continuing operations before income taxes (130,154 ) (5,020 ) (18,540 ) (7,182 ) (160,896 ) Segment capital expenditures 18,903 3,885 1,769 12 24,569 Three Months Ended September 30, 2014 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Oil and natural gas sales $ 153,815 $ — $ 7,702 $ — $ 161,517 Interest income 98 1 433 240 772 Depletion, depreciation, accretion and impairment 51,144 109 2,429 254 53,936 Income (loss) from continuing operations before income taxes 81,258 (3,345 ) 1,746 (8,957 ) 70,702 Segment capital expenditures 50,785 40,730 3,377 527 95,419 Nine Months Ended September 30, 2015 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Oil and natural gas sales $ 215,251 $ — $ 5,983 $ — $ 221,234 Interest income 221 2 218 628 1,069 Depletion, depreciation, accretion and impairment 265,297 41,588 52,565 1,170 360,620 Loss from continuing operations before income taxes (124,029 ) (48,723 ) (53,632 ) (17,072 ) (243,456 ) Segment capital expenditures 48,357 48,775 18,174 1,047 116,353 Nine Months Ended September 30, 2014 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Oil and natural gas sales $ 438,100 $ — $ 22,410 $ — $ 460,510 Interest income 419 1 1,292 448 2,160 Depletion, depreciation, accretion and impairment 131,742 420 7,249 726 140,137 Income (loss) from continuing operations before income taxes 229,750 (7,811 ) 7,446 (19,331 ) 210,054 Segment capital expenditures 147,016 103,535 17,176 1,132 268,859 As at September 30, 2015 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Property, plant and equipment $ 669,083 $ 94,460 $ 114,207 $ 4,514 $ 882,264 Goodwill 102,581 — — — 102,581 All other assets 133,776 21,822 11,255 119,170 286,023 Total Assets $ 905,440 $ 116,282 $ 125,462 $ 123,684 $ 1,270,868 As at December 31, 2014 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Property, plant and equipment $ 888,822 $ 87,028 $ 148,457 $ 4,637 $ 1,128,944 Goodwill 102,581 — — — 102,581 All other assets 157,549 40,613 14,724 269,639 482,525 Total Assets $ 1,148,952 $ 127,641 $ 163,181 $ 274,276 $ 1,714,050

Property, Plant and Equipment a

Property, Plant and Equipment and Inventory	9 Months Ended
	Sep. 30, 2015
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment and Inventory	Property, Plant and Equipment and Inventory Property, Plant and Equipment (Thousands of U.S. Dollars) As at September 30, 2015 As at December 31, 2014 Oil and natural gas properties Proved $ 1,940,596 $ 1,876,371 Unproved 326,717 316,856 2,267,313 2,193,227 Other 28,317 27,287 2,295,630 2,220,514 Accumulated depletion, depreciation and impairment (1,413,366 ) (1,091,570 ) $ 882,264 $ 1,128,944 In the three and nine months ended September 30, 2015 , the Company recorded ceiling test impairment losses of $129.4 million in its Colombia cost center, and $17.6 million and $46.9 million , respectively, in its Brazil cost center, related to lower oil prices. The Company follows the full cost method of accounting for its oil and gas properties. Under this method, the net book value of properties on a country-by-country basis, less related deferred income taxes, may not exceed a calculated “ceiling”. The ceiling is the estimated after tax future net revenues from proved oil and gas properties, discounted at 10% per year. In calculating discounted future net revenues, oil and natural gas prices are determined using the average price during the 12 months period prior to the ending date of the period covered by the balance sheet, calculated as an unweighted arithmetic average of the first-day-of-the month price for each month within such period for that oil and natural gas. That average price is then held constant, except for changes which are fixed and determinable by existing contracts. Therefore, ceiling test estimates are based on historical prices discounted at 10% per year and it should not be assumed that estimates of future net revenues represent the fair market value of the Company's reserves. In the three and nine months ended September 30, 2015 , the Company recorded impairment losses in its Peru cost center of $3.0 million and $41.0 million , respectively, related to costs incurred on Block 95. Inventory At September 30, 2015 , oil and supplies inventories were $17.4 million and $1.7 million , respectively ( December 31, 2014 - $15.2 million and $2.1 million , respectively). At September 30, 2015 , the Company had 429 Mbbl of oil inventory ( December 31, 2014 - 330 Mbbl).

Share Capital

Share Capital	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share Capital	Share Capital The Company’s authorized share capital consists of 595,000,002 shares of capital stock, of which 570 million are designated as Common Stock, par value $0.001 per share, 25 million are designated as Preferred Stock, par value $0.001 per share, and two shares are designated as special voting stock, par value $0.001 per share. Shares of Common Stock Exchangeable Shares of Gran Tierra Exchangeco Inc. Exchangeable Shares of Gran Tierra Goldstrike Inc. Balance, December 31, 2014 276,072,351 5,595,118 4,524,627 Options exercised 240,000 — — Shares repurchased and canceled (3,000,796 ) — — Exchange of exchangeable shares 1,502,995 (617,257 ) (885,738 ) Shares canceled (11 ) (84 ) — Balance, September 30, 2015 274,814,539 4,977,777 3,638,889 On July 22, 2015, the Company announced that it intended to implement a new share repurchase program (the “2015 Program”) through the facilities of the Toronto Stock Exchange ("TSX"), the NYSE MKT and eligible alternative trading platforms in Canada and the United States. The Company received regulatory approval from the TSX to commence the 2015 Program on July 27, 2015. The Company is able to purchase at prevailing market prices up to 13,831,866 shares of Common Stock, representing 4.98% of the issued and outstanding shares of Common Stock as of July 21, 2015. Shares purchased pursuant to the 2015 Program will be canceled. The 2015 Program will expire on July 29, 2016, or earlier if the 4.98% share maximum is reached. The 2015 Program may be terminated by the Company at any time, subject to compliance with regulatory requirements. As such, there can be no assurance regarding the total number of shares that may be repurchased under the 2015 Program. Income (loss) per share Basic income (loss) per share is calculated by dividing income (loss) attributable to common shareholders by the weighted average number of shares of Common Stock and exchangeable shares issued and outstanding during each period. Diluted income (loss) per share is calculated by adjusting the weighted average number of shares of Common Stock and exchangeable shares outstanding for the dilutive effect, if any, of share equivalents. The Company uses the treasury stock method to determine the dilutive effect. This method assumes that all Common Stock equivalents have been exercised at the beginning of the period (or at the time of issuance, if later), and that the funds obtained thereby were used to purchase shares of Common Stock of the Company at the volume weighted average trading price of shares of Common Stock during the period. Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Weighted average number of common and exchangeable shares outstanding 285,592,382 285,576,898 286,057,952 284,203,679 Weighted average shares issuable pursuant to stock options — 8,117,355 — 9,399,930 Weighted average shares assumed to be purchased from proceeds of stock options — (5,634,652 ) — (6,034,262 ) Weighted average number of diluted common and exchangeable shares outstanding 285,592,382 288,059,601 286,057,952 287,569,347 For the three and nine months ended September 30, 2015 , 13,051,834 and 13,659,367 options, respectively, on a weighted average basis, (three and nine months ended September 30, 2014 - 6,884,227 and 6,925,117 options, respectively) were excluded from the diluted income per share calculation as the options were anti-dilutive. Restricted Stock Units and Stock Options The Company grants time-vested restricted stock units ("RSUs") to certain officers, employees and consultants. Additionally, the Company grants options to purchase shares of Common Stock to certain directors, officers, employees and consultants. The following table provides information about RSU and stock option activity for the nine months ended September 30, 2015 : RSUs Options Number of Outstanding Share Units Number of Outstanding Options Weighted Average Exercise Price $/Option Balance, December 31, 2014 1,236,963 13,790,220 5.93 Granted 1,041,450 5,076,260 3.11 Exercised (519,111 ) (240,000 ) 2.51 Forfeited (708,242 ) (1,344,961 ) (5.66 ) Expired — (4,323,143 ) (6.85 ) Balance, September 30, 2015 1,051,060 12,958,376 4.61 For the nine months ended September 30, 2015 , 240,000 shares of Common Stock were issued for cash proceeds of $0.6 million upon the exercise of stock options ( nine months ended September 30, 2014 - $11.2 million ). The weighted average grant date fair value for options granted in the three months ended September 30, 2015 , was $0.95 ( three months ended September 30, 2014 - $2.21 ) and for the nine months ended September 30, 2015 , was $1.26 ( nine months ended September 30, 2014 - $2.50 ). The amounts recognized for stock-based compensation were as follows: Three Months Ended September 30, Nine Months Ended September 30, (Thousands of U.S. Dollars) 2015 2014 2015 2014 Compensation costs for stock options $ 967 $ 1,961 $ 1,654 $ 5,824 Compensation costs for RSUs 46 326 583 3,967 1,013 2,287 2,237 9,791 Less: Stock-based compensation costs capitalized — (278 ) (111 ) (2,100 ) Stock-based compensation expense $ 1,013 $ 2,009 $ 2,126 $ 7,691 Stock-based compensation expense for the three and nine months ended September 30, 2015 , and the three months ended September 30, 2014 , was primarily recorded in general and administrative ("G&A") expenses. Of the total stock-based compensation expense for the nine months ended September 30, 2014 , $6.1 million was recorded in G&A expenses, $0.3 million was recorded in operating expenses and $1.3 million was recorded in loss from discontinued operations. At September 30, 2015 , there was $5.3 million ( December 31, 2014 - $4.8 million ) of unrecognized compensation cost related to unvested stock options and RSUs which is expected to be recognized over a weighted average period of 1.5 years.

Asset Retirement Obligation

Asset Retirement Obligation	9 Months Ended
	Sep. 30, 2015
Asset Retirement Obligation [Abstract]
Asset Retirement Obligation	Asset Retirement Obligation Changes in the carrying amounts of the asset retirement obligation associated with the Company’s oil and natural gas properties were as follows: Nine Months Ended Year Ended (Thousands of U.S. Dollars) September 30, 2015 December 31, 2014 Balance, December 31, 2014 $ 35,812 $ 21,973 Settlements (6,368 ) (1,137 ) Liability incurred 1,030 11,956 Liabilities associated with the Argentina business unit sold (Note 3) — (10,170 ) Foreign exchange — (53 ) Accretion 960 1,406 Revisions in estimated liability 419 11,837 Balance, September 30, 2015 $ 31,853 $ 35,812 Asset retirement obligation - current $ 4,686 $ 8,026 Asset retirement obligation - long-term 27,167 27,786 $ 31,853 $ 35,812 For the nine months ended September 30, 2015 , settlements included cash payments of $4.8 million with the balance in accounts payable and accrued liabilities at September 30, 2015 . Revisions to estimated liabilities relate primarily to changes in estimates of asset retirement costs and include, but are not limited to, revisions of estimated inflation rates, changes in property lives and the expected timing of settling the asset retirement obligation. At September 30, 2015 , the fair value of assets that are legally restricted for purposes of settling the asset retirement obligation was $2.8 million ( December 31, 2014 - $2.0 million ). These assets are included in restricted cash on the Company's interim unaudited condensed consolidated balance sheets.

Taxes

Taxes	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Taxes	Taxes The Company's effective tax rate was 24% in the nine months ended September 30, 2015 , compared with 40% in the comparable period in 2014 . The Company's effective tax rate differed from the U.S. statutory rate of 35% primarily due to an increase in the valuation allowance, which was largely attributable to 2015 impairment losses in Brazil and Peru and an increase in the tax rate in Canada, as well as non-deductible third party royalty in Colombia and other local taxes. These were partially offset by the impact of foreign taxes and other permanent differences. On December 23, 2014, the Colombian Congress passed a law which imposes an equity tax levied on Colombian operations for 2015, 2016 and 2017. The equity tax is calculated based on a legislated measure, which is based on the Company’s Colombian legal entities' balance sheet equity for tax purposes at January 1, 2015. This measure is subject to adjustment for inflation in future years. The equity tax rates for January 1, 2015, 2016 and 2017, are 1.15% , 1% and 0.4% , respectively. The legal obligation for each year's equity tax liability arises on January 1 of each year; therefore, the Company recognized the annual amount of $3.8 million for the equity tax expense in the consolidated statement of operations during the three months ended March 31, 2015, and a corresponding payable on the consolidated balance sheet at March 31, 2015. This amount was paid in May and September 2015 and at September 30, 2015 , accounts payable included $ nil (December 31, 2014 - $nil ).

Contingencies

Contingencies	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies Gran Tierra’s production from the Costayaco Exploitation Area is subject to an additional royalty (the "HPR royalty"), which applies when cumulative gross production from an Exploitation Area is greater than five MMbbl . The HPR royalty is calculated on the difference between a trigger price defined in the Chaza Block exploration and production contract (the "Chaza Contract") and the sales price. The Agencia Nacional de Hidrocarburos (National Hydrocarbons Agency) (“ANH”) has interpreted the Chaza Contract as requiring that the HPR royalty must be paid with respect to all production from the Moqueta Exploitation Area and initiated a noncompliance procedure under the Chaza Contract, which was contested by Gran Tierra because the Moqueta Exploitation Area and the Costayaco Exploitation Area are separate Exploitation Areas. ANH did not proceed with that noncompliance procedure. Gran Tierra also believes that the evidence shows that the Costayaco and Moqueta Fields are two clearly separate and independent hydrocarbon accumulations. Therefore, it is Gran Tierra’s view that, pursuant to the terms of the Chaza Contract, the HPR royalty is only to be paid with respect to production from the Moqueta Exploitation Area when the accumulated oil production from that Exploitation Area exceeds five MMbbl. Discussions with the ANH have not resolved this issue and Gran Tierra has initiated the dispute resolution process under the Chaza Contract by filing on January 14, 2013, an arbitration claim before the Center for Arbitration and Conciliation of the Chamber of Commerce of Bogotá, Colombia, seeking a decision that the HPR royalty is not payable until production from the Moqueta Exploitation Area exceeds five MMbbl . Gran Tierra supplemented its claim on May 30, 2013. The ANH filed a response to the claim seeking a declaration that its interpretation is correct and a counterclaim seeking, amongst other remedies, declarations that Gran Tierra breached the Chaza Contract by not paying the disputed HPR royalty, that the amount of the alleged HPR royalty is payable, and that the Chaza Contract be terminated. Gran Tierra filed a response to the ANH's counterclaim and filed its comments on the ANH's responses to Gran Tierra's claim. The ANH filed an amended counterclaim and Gran Tierra filed a response to the ANH's amended counterclaim. On April 30, 2015, total cumulative production from the Moqueta Exploitation Area reached 5.0 MMbbl and Gran Tierra commenced paying the HPR royalty payable on production over that threshold. The estimated compensation which would be payable on cumulative production if the ANH's claims are accepted in the arbitration is $66.3 million plus related interest of $23.6 million . Gran Tierra also disagrees with the interest rate that the ANH has used in calculating the interest cost. Gran Tierra asserts that since the HPR royalty is denominated in the U.S. dollar, the contract requires the interest rate to be three-month LIBOR plus 4% , whereas the ANH has applied the highest legally authorized interest rate on Colombian peso liabilities, which during the period of production to date has averaged approximately 29% per annum. At September 30, 2015 , based on an interest rate of three-month LIBOR plus 4% related interest would be $5.7 million . At this time no amount has been accrued in the interim unaudited condensed consolidated financial statements nor deducted from the Company's reserves for the disputed HPR royalty as Gran Tierra does not consider it probable that a loss will be incurred. Additionally, the ANH and Gran Tierra are engaged in discussions regarding the interpretation of whether certain transportation and related costs are eligible to be deducted in the calculation of the HPR royalty. Discussions with the ANH are ongoing. Based on the Company's understanding of the ANH's position, the estimated compensation which would be payable if the ANH’s interpretation is correct could be up to $43.6 million as at September 30, 2015 . At this time no amount has been accrued in the interim unaudited condensed consolidated financial statements as Gran Tierra does not consider it probable that a loss will be incurred. Gran Tierra Energy Colombia, Ltd. and Petrolifera Petroleum (Colombia) Ltd (collectively “GTEC”) and Ecopetrol, the contracting parties of the Guayuyaco Association Contract, are engaged in a dispute regarding the interpretation of the procedure for allocation of oil produced and sold during the long-term test of the Guayuyaco-1 and Guayuyaco-2 wells, prior to GTEC's purchase of the companies originally involved in the dispute. There was no agreement between the parties, and Ecopetrol filed a lawsuit in the Contravention Administrative Tribunal in the District of Cauca (the "Tribunal") regarding this matter. During 2013, the Tribunal ruled in favor of Ecopetrol and awarded Ecopetrol 44,025 bbl of oil. GTEC has filed an appeal of the ruling to the Supreme Administrative Court (Consejo de Estado) in a second instance procedure. At September 30, 2015 , and December 31, 2014 , Gran Tierra had accrued $2.4 million in the interim unaudited condensed consolidated financial statements in relation to this dispute. The Company provided the purchaser of its Argentina business unit with certain indemnifications. The Company remains responsible for certain contingent liabilities related to such indemnifications, subject to defined limitations. The Company does not believe that these obligations are probable of having a material impact on its consolidated financial position, results of operations or cash flows. In addition to the above, Gran Tierra has a number of other lawsuits and claims pending. Although the outcome of these other lawsuits and disputes cannot be predicted with certainty, Gran Tierra believes the resolution of these matters would not have a material adverse effect on the Company’s consolidated financial position, results of operations or cash flows. Gran Tierra records costs as they are incurred or become probable and determinable. Letters of credit At September 30, 2015 , the Company had provided promissory notes totaling $75.7 million ( December 31, 2014 - $86.3 million ) as security for letters of credit relating to work commitment guarantees contained in exploration contracts and other capital or operating requirements .

Financial Instruments, Fair Val

Financial Instruments, Fair Value Measurements, Credit Risk and Foreign Exchange Risk	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Financial Instruments, Fair Value Measurements, Credit Risk and Foreign Exchange Risk	Financial Instruments, Fair Value Measurement, Credit Risk and Foreign Exchange Risk Financial Instruments At September 30, 2015 , the Company’s financial instruments recognized in the balance sheet consist of cash and cash equivalents, restricted cash, accounts receivable, trading securities, accounts payable, accrued liabilities and contingent consideration included in other long-term liabilities. Fair Value Measurement The fair value of trading securities and contingent consideration are being remeasured at the estimated fair value at the end of each reporting period. The fair value of the trading securities which were received as consideration on the sale of the Company's Argentina business unit was estimated based on quoted market prices in an active market. The fair value of the contingent consideration, which relates to the acquisition of the remaining 30% working interest in certain properties in Brazil, was estimated based on the consideration expected to be transferred and discounted back to present value by applying an appropriate discount rate that reflected the risk factors associated with the payment streams. The discount rate used was determined in accordance with accepted valuation methods. The fair value of foreign currency derivatives was based on the estimated maturity value of foreign exchange non-deliverable forward contracts using applicable forward exchange rates. The most significant variable to the cash flow calculations is the estimation of forward foreign exchange rates. The resulting future cash inflows or outflows at maturity of the contracts are the net value of the contract. The fair value of the trading securities, foreign currency derivative liability and contingent consideration at September 30, 2015 , and December 31, 2014 , were as follows: As at (Thousands of U.S. Dollars) September 30, 2015 December 31, 2014 Trading securities $ 7,016 $ 7,586 Foreign currency derivative liability $ — $ 3,057 Contingent consideration liability 1,061 1,061 $ 1,061 $ 4,118 The following table presents gains or losses on financial instruments recognized in the accompanying interim unaudited condensed consolidated statements of operations: Three Months Ended September 30, Nine Months Ended September 30, (Thousands of U.S. Dollars) 2015 2014 2015 2014 Trading securities loss $ 2,670 $ 2,540 $ 570 $ 2,201 Foreign currency derivatives loss (gain) — 250 692 (4,424 ) $ 2,670 $ 2,790 $ 1,262 $ (2,223 ) These gains and losses are presented as financial instruments gains or losses in the interim unaudited condensed consolidated statements of operations and cash flows. There were no sales of trading securities in the nine months ended September 30, 2015 , and the trading securities loss represents an unrealized loss . The fair value of long-term restricted cash approximates its carrying value because interest rates are variable and reflective of market rates. The fair values of other financial instruments approximate their carrying amounts due to the short-term maturity of these instruments. GAAP establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. This hierarchy consists of three broad levels. Level 1 inputs consist of quoted prices (unadjusted) in active markets for identical assets and liabilities and have the highest priority. Level 2 and 3 inputs are based on significant other observable inputs and significant unobservable inputs, respectively, and have lower priorities. The Company uses appropriate valuation techniques based on the available inputs to measure the fair values of assets and liabilities. At September 30, 2015 , and December 31, 2014 , the fair value of the trading securities acquired in connection with the disposal of the Argentina business unit was determined using Level 1 inputs. At December 31, 2014 , the fair value of the foreign currency derivative was determined using Level 2 inputs. At September 30, 2015 , and December 31, 2014 , the fair value of the contingent consideration payable in connection with the Brazil acquisition was determined using Level 3 inputs. The disclosure in the paragraph above regarding the fair value of cash and restricted cash was based on Level 1 inputs. The Company’s non-recurring fair value measurements include asset retirement obligations. The fair value of an asset retirement obligation is measured by reference to the expected future cash outflows required to satisfy the retirement obligation discounted at the Company’s credit-adjusted risk-free interest rate. The significant level 3 inputs used to calculate such liabilities include estimates of costs to be incurred, the Company’s credit-adjusted risk-free interest rate, inflation rates and estimated dates of abandonment. Accretion expense is recognized over time as the discounted liabilities are accreted to their expected settlement value, while the asset retirement cost is amortized over the estimated productive life of the related assets. Foreign Exchange Rate Risk Unrealized foreign exchange gains and losses primarily result from fluctuation of the U.S. dollar to the Colombian peso due to Gran Tierra’s current and deferred tax liabilities, which are monetary liabilities mainly denominated in the local currency of the Colombian operations. As a result, foreign exchange gains and losses must be calculated on conversion to the U.S. dollar functional currency. A strengthening in the Colombian peso against the U.S. dollar results in foreign exchange losses, estimated at $24,000 for each one peso decrease in the exchange rate of the Colombian peso to one U.S. dollar . From time to time, the Company purchases non-deliverable forward contracts for purposes of fixing exchange rates at which it will purchase or sell Colombian pesos to settle its income tax installment payments. At September 30, 2015 , the Company did not have any open foreign currency derivative positions. With the exception of these foreign currency derivatives, any foreign currency transactions are conducted on a spot basis with major financial institutions in the Company’s operating areas. For the nine months ended September 30, 2015 , 97% ( nine months ended September 30, 2014 - 95% ) of the Company's revenue and other income was generated in Colombia. In Colombia, the Company receives 100% of its revenues in U.S. dollars and the majority of its capital expenditures are in U.S. dollars or are based on U.S. dollar prices. In Brazil, prices for oil are in U.S. dollars, but revenues are received in local currency translated according to current exchange rates. The majority of the Company's capital expenditures within Brazil are based on U.S. dollar prices, but are paid in local currency translated according to current exchange rates. In Peru, capital expenditures are based on U.S. dollar prices and may be paid in local currency or U.S. dollars. Credit Risk Credit risk arises from the potential that the Company may incur a loss if a counterparty to a financial instrument fails to meet its obligation in accordance with agreed terms. The Company’s financial instruments that are exposed to concentrations of credit risk consist primarily of cash and accounts receivables. The carrying value of cash and accounts receivable reflects management’s assessment of credit risk . At September 30, 2015 , cash and cash equivalents and restricted cash included balances in savings and checking accounts, as well as term deposits and certificates of deposit, placed with financial institutions with strong investment grade ratings or governments, or the equivalent in the Company’s operating areas.

Severance Costs

Severance Costs	9 Months Ended
	Sep. 30, 2015
Restructuring and Related Activities [Abstract]
Severance Costs	Severance Costs In March 2015, the Company significantly reduced the number of its full-time employees. Staff reductions as part of this cost cutting measure were substantially completed at March 31, 2015. Additional employee terminations occurred during the three months ended June 30, 2015, and the three months ended September 30, 2015. Employee termination benefits were recorded as incurred based on existing employee contracts, statutory requirements, completed negotiations and company policy. Severance costs for the Company’s reportable segments and other activities for the three and nine months ended September 30, 2015 , were as follows: Three Months Ended September 30, 2015 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Severance expenses $ — $ 439 $ — $ 22 $ 461 Nine Months Ended September 30, 2015 Colombia Peru Brazil All Other Total Severance expenses $ 1,237 $ 1,863 $ 109 $ 3,618 $ 6,827 The amounts in the table for the nine months ended September 30, 2015 , represent cumulative costs incurred to date and exclude the impact of the reversal of stock-based compensation expense for unvested options of terminated employees which was recorded in G&A expenses. Changes in the severance cost related liability were as follows: (Thousands of U.S. Dollars) Nine Months Ended September 30, 2015 Balance, December 31, 2014 $ — Liability incurred 6,827 Settlements (6,827 ) Balance, September 30, 2015 $ —

Credit Facility

Credit Facility	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Credit Facility	Credit Facility At September 30, 2015 , the Company had a credit facility with a syndicate of lenders. Availability under the credit facility is determined by a proven reserves-based borrowing base, and remains subject to the satisfaction of conditions precedent set forth in the credit agreement. Loans under the credit agreement will mature on September 18, 2018. The initial borrowing base is $200 million , and the borrowing base will be re-determined semi-annually based on reserve evaluation reports, subject to a maximum of $500 million . The borrowing base for the credit facility is supported by the present value of the petroleum reserves of two of the Company's subsidiaries with operating branches in Colombia. The credit agreement includes a letter of credit sub-limit of up to $100 million . Amounts drawn down under the facility bear interest, at the Company's option, at the USD LIBOR rate plus a margin ranging from 2.00% per annum to 3.00% per annum, or an alternate base rate plus a margin ranging from 1.00% per annum to 2.00% per annum, in each case based on the borrowing base utilization percentage. Undrawn amounts under the credit facility bear interest at 0.75% per annum, based on the average daily amount of unused commitments. A letter of credit participation fee of 0.25% per annum will accrue on the average daily amount of letter of credit exposure. Under the terms of the credit facility, the Company is required to maintain and was in compliance with certain financial and operating covenants. No amounts have been drawn on this facility. This credit facility was entered into and became effective on September 18, 2015, and replaced the Company's previous credit facility which was canceled on this date.

Significant Accounting Polici19

Significant Accounting Policies a (Policies)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements Simplifying the Measurement of Inventory In July 2015, the FASB issued ASU 2015-11, “ Simplifying the Measurement of Inventory ". The ASU provides guidance for the subsequent measurement of inventory and requires that inventory that is measured using average cost be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The ASU will be effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. The implementation of this update is not expected to materially impact the Company’s consolidated financial position, results of operations or cash flows or disclosure.

Discontinued Operations (Tables

Discontinued Operations (Tables)	9 Months Ended
	Sep. 30, 2015
Discontinued Operations and Disposal Groups [Abstract]
Financial disclosures of discontinued operations	Revenue and other income and loss from discontinued operations, net of income taxes, for the nine months ended September 30, 2014 , were as follows: (Thousands of U.S. Dollars) Nine Months Ended September 30, 2014 Revenue and other income $ 31,985 Loss from operations of discontinued operations before income taxes $ (6,252 ) Income tax expense (1,458 ) Loss from operations of discontinued operations (7,710 ) Loss on sale before income taxes (18,235 ) Income tax expense (1,045 ) Loss on sale (19,280 ) Loss from discontinued operations, net of income taxes $ (26,990 )

Segment and Geographic Report21

Segment and Geographic Reporting (Tables)	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Reportable Geographic Segments	The following tables present information on the Company’s reportable segments and other activities: Three Months Ended September 30, 2015 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Oil and natural gas sales $ 73,557 $ — $ 2,096 $ — $ 75,653 Interest income 61 — — 205 266 Depletion, depreciation, accretion and impairment 181,981 3,208 19,396 408 204,993 Loss from continuing operations before income taxes (130,154 ) (5,020 ) (18,540 ) (7,182 ) (160,896 ) Segment capital expenditures 18,903 3,885 1,769 12 24,569 Three Months Ended September 30, 2014 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Oil and natural gas sales $ 153,815 $ — $ 7,702 $ — $ 161,517 Interest income 98 1 433 240 772 Depletion, depreciation, accretion and impairment 51,144 109 2,429 254 53,936 Income (loss) from continuing operations before income taxes 81,258 (3,345 ) 1,746 (8,957 ) 70,702 Segment capital expenditures 50,785 40,730 3,377 527 95,419 Nine Months Ended September 30, 2015 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Oil and natural gas sales $ 215,251 $ — $ 5,983 $ — $ 221,234 Interest income 221 2 218 628 1,069 Depletion, depreciation, accretion and impairment 265,297 41,588 52,565 1,170 360,620 Loss from continuing operations before income taxes (124,029 ) (48,723 ) (53,632 ) (17,072 ) (243,456 ) Segment capital expenditures 48,357 48,775 18,174 1,047 116,353 Nine Months Ended September 30, 2014 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Oil and natural gas sales $ 438,100 $ — $ 22,410 $ — $ 460,510 Interest income 419 1 1,292 448 2,160 Depletion, depreciation, accretion and impairment 131,742 420 7,249 726 140,137 Income (loss) from continuing operations before income taxes 229,750 (7,811 ) 7,446 (19,331 ) 210,054 Segment capital expenditures 147,016 103,535 17,176 1,132 268,859
Long-lived Assets by Geographical Area	As at September 30, 2015 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Property, plant and equipment $ 669,083 $ 94,460 $ 114,207 $ 4,514 $ 882,264 Goodwill 102,581 — — — 102,581 All other assets 133,776 21,822 11,255 119,170 286,023 Total Assets $ 905,440 $ 116,282 $ 125,462 $ 123,684 $ 1,270,868 As at December 31, 2014 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Property, plant and equipment $ 888,822 $ 87,028 $ 148,457 $ 4,637 $ 1,128,944 Goodwill 102,581 — — — 102,581 All other assets 157,549 40,613 14,724 269,639 482,525 Total Assets $ 1,148,952 $ 127,641 $ 163,181 $ 274,276 $ 1,714,050

Property, Plant and Equipment22

Property, Plant and Equipment and Inventory (Tables)	9 Months Ended
	Sep. 30, 2015
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	Property, Plant and Equipment (Thousands of U.S. Dollars) As at September 30, 2015 As at December 31, 2014 Oil and natural gas properties Proved $ 1,940,596 $ 1,876,371 Unproved 326,717 316,856 2,267,313 2,193,227 Other 28,317 27,287 2,295,630 2,220,514 Accumulated depletion, depreciation and impairment (1,413,366 ) (1,091,570 ) $ 882,264 $ 1,128,944

Share Capital (Tables)

Share Capital (Tables)	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [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, 2014 276,072,351 5,595,118 4,524,627 Options exercised 240,000 — — Shares repurchased and canceled (3,000,796 ) — — Exchange of exchangeable shares 1,502,995 (617,257 ) (885,738 ) Shares canceled (11 ) (84 ) — Balance, September 30, 2015 274,814,539 4,977,777 3,638,889
Weighted average shares outstanding	Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Weighted average number of common and exchangeable shares outstanding 285,592,382 285,576,898 286,057,952 284,203,679 Weighted average shares issuable pursuant to stock options — 8,117,355 — 9,399,930 Weighted average shares assumed to be purchased from proceeds of stock options — (5,634,652 ) — (6,034,262 ) Weighted average number of diluted common and exchangeable shares outstanding 285,592,382 288,059,601 286,057,952 287,569,347
RSU's and Stock options outstanding	The following table provides information about RSU and stock option activity for the nine months ended September 30, 2015 : RSUs Options Number of Outstanding Share Units Number of Outstanding Options Weighted Average Exercise Price $/Option Balance, December 31, 2014 1,236,963 13,790,220 5.93 Granted 1,041,450 5,076,260 3.11 Exercised (519,111 ) (240,000 ) 2.51 Forfeited (708,242 ) (1,344,961 ) (5.66 ) Expired — (4,323,143 ) (6.85 ) Balance, September 30, 2015 1,051,060 12,958,376 4.61
Amounts recognized for stock-based compensation	The amounts recognized for stock-based compensation were as follows: Three Months Ended September 30, Nine Months Ended September 30, (Thousands of U.S. Dollars) 2015 2014 2015 2014 Compensation costs for stock options $ 967 $ 1,961 $ 1,654 $ 5,824 Compensation costs for RSUs 46 326 583 3,967 1,013 2,287 2,237 9,791 Less: Stock-based compensation costs capitalized — (278 ) (111 ) (2,100 ) Stock-based compensation expense $ 1,013 $ 2,009 $ 2,126 $ 7,691

Asset Retirement Obligation (Ta

Asset Retirement Obligation (Tables)	9 Months Ended
	Sep. 30, 2015
Asset Retirement Obligation [Abstract]
Changes in Asset Retirement Obligations	Changes in the carrying amounts of the asset retirement obligation associated with the Company’s oil and natural gas properties were as follows: Nine Months Ended Year Ended (Thousands of U.S. Dollars) September 30, 2015 December 31, 2014 Balance, December 31, 2014 $ 35,812 $ 21,973 Settlements (6,368 ) (1,137 ) Liability incurred 1,030 11,956 Liabilities associated with the Argentina business unit sold (Note 3) — (10,170 ) Foreign exchange — (53 ) Accretion 960 1,406 Revisions in estimated liability 419 11,837 Balance, September 30, 2015 $ 31,853 $ 35,812 Asset retirement obligation - current $ 4,686 $ 8,026 Asset retirement obligation - long-term 27,167 27,786 $ 31,853 $ 35,812

Financial Instruments, Fair V25

Financial Instruments, Fair Value Measurements, Credit Risk and Foreign Exchange Risk (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value of Foreign Currency Derivatives, Contingent Consideration and Contingent Liability	The fair value of the trading securities, foreign currency derivative liability and contingent consideration at September 30, 2015 , and December 31, 2014 , were as follows: As at (Thousands of U.S. Dollars) September 30, 2015 December 31, 2014 Trading securities $ 7,016 $ 7,586 Foreign currency derivative liability $ — $ 3,057 Contingent consideration liability 1,061 1,061 $ 1,061 $ 4,118
Gains Associated with Foreign Currency Derivatives	The following table presents gains or losses on financial instruments recognized in the accompanying interim unaudited condensed consolidated statements of operations: Three Months Ended September 30, Nine Months Ended September 30, (Thousands of U.S. Dollars) 2015 2014 2015 2014 Trading securities loss $ 2,670 $ 2,540 $ 570 $ 2,201 Foreign currency derivatives loss (gain) — 250 692 (4,424 ) $ 2,670 $ 2,790 $ 1,262 $ (2,223 )

Severance Costs (Tables)

Severance Costs (Tables)	9 Months Ended
	Sep. 30, 2015
Restructuring and Related Activities [Abstract]
Severance costs by segment	Severance costs for the Company’s reportable segments and other activities for the three and nine months ended September 30, 2015 , were as follows: Three Months Ended September 30, 2015 (Thousands of U.S. Dollars) Colombia Peru Brazil All Other Total Severance expenses $ — $ 439 $ — $ 22 $ 461 Nine Months Ended September 30, 2015 Colombia Peru Brazil All Other Total Severance expenses $ 1,237 $ 1,863 $ 109 $ 3,618 $ 6,827
Change in severance cost liability	Changes in the severance cost related liability were as follows: (Thousands of U.S. Dollars) Nine Months Ended September 30, 2015 Balance, December 31, 2014 $ — Liability incurred 6,827 Settlements (6,827 ) Balance, September 30, 2015 $ —

Discontinued Operations - Reven

Discontinued Operations - Revenue and Loss from Discontinued Operations (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2014USD ($)
Discontinued Operations and Disposal Groups [Abstract]
Revenue and other income	$ 31,985
Loss from operations of discontinued operations before income taxes	(6,252)
Income tax expense	(1,458)
Loss from operations of discontinued operations	(7,710)
Loss on sale before income taxes	(18,235)
Income tax expense	(1,045)
Loss on sale	(19,280)
Loss from discontinued operations, net of income taxes	$ (26,990)

Discontinued Operations - Narra

Discontinued Operations - Narrative (Details) - Argentina Business Unit [Member] $ in Millions	Jun. 25, 2014USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Aggregate consideration	$ 69.3
Cash received	55.4
GTE ULC and PCESA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Value of shares received	$ 13.9

Segment and Geographic Report29

Segment and Geographic Reporting - Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Oil and natural gas sales	$ 75,653	$ 161,517	$ 221,234	$ 460,510
Interest income	266	772	1,069	2,160
Depletion, depreciation, accretion and impairment	204,993	53,936	360,620	140,137
Loss from continuing operations before income taxes	(160,896)	70,702	(243,456)	210,054
Continuing Operations [Member]
Segment Reporting Information [Line Items]
Oil and natural gas sales	75,653	161,517	221,234	460,510
Interest income	266	772	1,069	2,160
Depletion, depreciation, accretion and impairment	204,993	53,936	360,620	140,137
Loss from continuing operations before income taxes	(160,896)	70,702	(243,456)	210,054
Segment capital expenditures	24,569	95,419	116,353	268,859
Colombia [Member] | Continuing Operations [Member]
Segment Reporting Information [Line Items]
Oil and natural gas sales	73,557	153,815	215,251	438,100
Interest income	61	98	221	419
Depletion, depreciation, accretion and impairment	181,981	51,144	265,297	131,742
Loss from continuing operations before income taxes	(130,154)	81,258	(124,029)	229,750
Segment capital expenditures	18,903	50,785	48,357	147,016
Peru [Member] | Continuing Operations [Member]
Segment Reporting Information [Line Items]
Oil and natural gas sales	0	0	0	0
Interest income	0	1	2	1
Depletion, depreciation, accretion and impairment	3,208	109	41,588	420
Loss from continuing operations before income taxes	(5,020)	(3,345)	(48,723)	(7,811)
Segment capital expenditures	3,885	40,730	48,775	103,535
Brazil [Member] | Continuing Operations [Member]
Segment Reporting Information [Line Items]
Oil and natural gas sales	2,096	7,702	5,983	22,410
Interest income	0	433	218	1,292
Depletion, depreciation, accretion and impairment	19,396	2,429	52,565	7,249
Loss from continuing operations before income taxes	(18,540)	1,746	(53,632)	7,446
Segment capital expenditures	1,769	3,377	18,174	17,176
All Other [Member] | Continuing Operations [Member]
Segment Reporting Information [Line Items]
Oil and natural gas sales	0	0	0	0
Interest income	205	240	628	448
Depletion, depreciation, accretion and impairment	408	254	1,170	726
Loss from continuing operations before income taxes	(7,182)	(8,957)	(17,072)	(19,331)
Segment capital expenditures	$ 12	$ 527	$ 1,047	$ 1,132

Segment and Geographic Report30

Segment and Geographic Reporting - Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Property, plant and equipment	$ 882,264	$ 1,128,944
Goodwill	102,581	102,581
Total Assets	1,270,868	1,714,050
Continuing Operations [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment	882,264	1,128,944
Goodwill	102,581	102,581
All other assets	286,023	482,525
Total Assets	1,270,868	1,714,050
Continuing Operations [Member] | Colombia [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment	669,083	888,822
Goodwill	102,581	102,581
All other assets	133,776	157,549
Total Assets	905,440	1,148,952
Continuing Operations [Member] | Peru [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment	94,460	87,028
Goodwill	0	0
All other assets	21,822	40,613
Total Assets	116,282	127,641
Continuing Operations [Member] | Brazil [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment	114,207	148,457
Goodwill	0	0
All other assets	11,255	14,724
Total Assets	125,462	163,181
Continuing Operations [Member] | All Other [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment	4,514	4,637
Goodwill	0	0
All other assets	119,170	269,639
Total Assets	$ 123,684	$ 274,276

Property, Plant and Equipment31

Property, Plant and Equipment and Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Oil and natural gas properties	$ 2,295,630	$ 2,220,514
Accumulated depletion, depreciation and impairment	(1,413,366)	(1,091,570)
Total Property, Plant and Equipment	882,264	1,128,944
Proved [Member]
Property, Plant and Equipment [Line Items]
Oil and natural gas properties	1,940,596	1,876,371
Unproved [Member]
Property, Plant and Equipment [Line Items]
Oil and natural gas properties	326,717	316,856
Oil and natural gas properties depletable base under full cost accounting [Member]
Property, Plant and Equipment [Line Items]
Oil and natural gas properties	2,267,313	2,193,227
Furniture and fixtures and leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Oil and natural gas properties	$ 28,317	$ 27,287

Property, Plant and Equipment32

Property, Plant and Equipment and Inventory - Narrative (Details) bbl in Thousands, $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015USD ($)bbl	Sep. 30, 2015USD ($)bbl	Dec. 31, 2014USD ($)bbl
Property, Plant and Equipment [Line Items]
Crude oil inventories	$ 17.4	$ 17.4	$ 15.2
Supplies	$ 1.7	$ 1.7	$ 2.1
Oil inventory (in bbl) | bbl	429	429	330
Colombia [Member]
Property, Plant and Equipment [Line Items]
Impairment loss	$ 129.4	$ 161
Brazil [Member]
Property, Plant and Equipment [Line Items]
Impairment loss	17.6	$ 46.9
Brazil [Member] | Oil and natural gas properties depletable base under full cost accounting [Member] | Assets [Member] | Income Approach Valuation Technique [Member]
Property, Plant and Equipment [Line Items]
Discount rate (percent)		10.00%
Peru [Member] | Block 95 [Member]
Property, Plant and Equipment [Line Items]
Impairment loss	$ 3	$ 41

Share Capital - Shares of Commo

Share Capital - Shares of Common Stock (Details)	9 Months Ended
	Sep. 30, 2015shares
Increase (Decrease) in Common Stock
Beginning balance	276,072,351
Options exercised	240,000
Ending balance	274,814,539
Common Stock [Member]
Increase (Decrease) in Common Stock
Beginning balance	276,072,351
Options exercised	240,000
Shares repurchased and canceled	(3,000,796)
Exchange of exchangeable shares	1,502,995
Shares canceled	(11)
Ending balance	274,814,539
Common Stock [Member] | Gran Tierra Exchangeco Inc [Member]
Increase (Decrease) in Common Stock
Beginning balance	5,595,118
Options exercised	0
Shares repurchased and canceled	0
Exchange of exchangeable shares	(617,257)
Shares canceled	(84)
Ending balance	4,977,777
Common Stock [Member] | Gran Tierra Goldstrike Inc [Member]
Increase (Decrease) in Common Stock
Beginning balance	4,524,627
Options exercised	0
Shares repurchased and canceled	0
Exchange of exchangeable shares	(885,738)
Shares canceled	0
Ending balance	3,638,889

Share Capital - Weighted Averag

Share Capital - Weighted Average Shares (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Weighted average number of common and exchangeable shares outstanding	285,592,382	285,576,898	286,057,952	284,203,679
Weighted average shares issuable pursuant to stock options	0	8,117,355	0	9,399,930
Weighted average shares assumed to be purchased from proceeds of stock options	0	(5,634,652)	0	(6,034,262)
Weighted average number of diluted common and exchangeable shares outstanding	285,592,382	288,059,601	286,057,952	287,569,347

Share Capital - RSU and Stock O

Share Capital - RSU and Stock Option Activity (Details)	9 Months Ended
	Sep. 30, 2015$ / sharesshares
Number of Outstanding Options
Beginning Balance (in shares)	13,790,220
Granted (in shares)	5,076,260
Exercised (in shares)	(240,000)
Forfeited (in shares)	(1,344,961)
Expired (in shares)	(4,323,143)
Ending Balance (in shares)	12,958,376
Weighted Average Exercise Price $/Option
Weighted Average Exercise Price $/Option, beginning balance (in dollars per share) | $ / shares	$ 5.93
Weighted Average Exercise Price $/Option, Granted (in dollars per share) | $ / shares	3.11
Weighted Average Exercise Price $/Options, Exercised (in dollars per share) | $ / shares	2.51
Weighted Average Exercise Price $/Options, Forfeited (in dollars per share) | $ / shares	(5.66)
Weighted Average Exercise Price $/Options, Expired (in dollars per share) | $ / shares	(6.85)
Weighted Average Exercise Price $/Option, ending balance (in dollars per share) | $ / shares	$ 4.61
RSUs [Member]
Number of Outstanding Share Units
Beginning Balance (in shares)	1,236,963
Granted (in shares)	1,041,450
Exercised (in shares)	(519,111)
Forfeited (in shares)	(708,242)
Expired (in shares)	0
Ending Balance (in shares)	1,051,060

Share Capital - Allocation of S

Share Capital - Allocation of Share Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost	$ 1,013	$ 2,287	$ 2,237	$ 9,791
Less: Stock-based compensation costs capitalized	0	(278)	(111)	(2,100)
Stock-based compensation expense	1,013	2,009	2,126	7,691
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost	967	1,961	1,654	5,824
RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost	$ 46	$ 326	$ 583	$ 3,967

Share Capital - Narrative (Deta

Share Capital - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jul. 27, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercised (in shares)			240,000
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Authorized share capital	595,000,002		595,000,002
Common stock, authorized	570,000,000		570,000,000
Common shares, par value (in dollars per share)	$ 0.001		$ 0.001			$ 0.001
Preferred stock, authorized	25,000,000		25,000,000
Preferred stock, par value (in dollars per share)	$ 0.001		$ 0.001
Stock repurchase program amount authorized (shares)					$ 13,831,866
Common stock shares issued and outstanding, (percent)					4.98%
Special voting stock-authorized (in shares)	2		2
Special voting stock-par value (in dollars per share)	$ 0.001		$ 0.001
Common shares, outstanding	274,814,539		274,814,539			276,072,351
Proceeds from issuance of shares of Common Stock			$ 602,000	$ 11,177,000
Stock Options [Abstract]
Stock-based compensation expense	$ 1,013,000	$ 2,009,000	2,126,000	$ 7,691,000
Unrecognized compensation cost related to unvested stock options	$ 5,300,000		$ 5,300,000			$ 4,800,000
Unvested stock options recognition period			1 year 6 months
Stock Options [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Weighted Average Grant Date Fair Value $/Option, Granted in Period	$ 0.95	$ 2.21	$ 1.26	$ 2.50
Earnings Per Share [Abstract]
Options excluded from the diluted income per share calculation	13,051,834	6,884,227	13,659,367	6,925,117
Stock Options [Member] | General and Administrative Expense [Member]
Stock Options [Abstract]
Stock-based compensation expense				$ 6,100,000
Stock Options [Member] | Operating Expense [Member]
Stock Options [Abstract]
Stock-based compensation expense				300,000
Stock Options [Member] | Discontinued Operations [Member]
Stock Options [Abstract]
Stock-based compensation expense				$ 1,300,000

Asset Retirement Obligation (De

Asset Retirement Obligation (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Sep. 30, 2015	Dec. 31, 2014
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning Balance	$ 35,812	$ 21,973	$ 21,973
Settlements	(6,368)		(1,137)
Liability incurred	1,030		11,956
Liabilities associated with the Argentina business unit sold	0		(10,170)
Foreign exchange	0		(53)
Accretion	960		1,406
Revisions in estimated liability	419		11,837
Asset retirement obligation - current				$ 4,686	$ 8,026
Asset retirement obligation - long-term				27,167	27,786
Balance, end of period	35,812	21,973	$ 21,973	31,853	35,812
Cash settlement of asset retirement obligation	$ (4,768)	$ (211)
Fair value of legally restricted assets				$ 2,800	$ 2,000

Taxes - Narrative (Details)

Taxes - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Income Tax Examination [Line Items]
Effective tax rate (percent)				(24.00%)	(40.00%)
U.S. Statutory rate (percent)				35.00%
Foreign equity tax expense	$ 0	$ 3,769	$ 0	$ 3,769	$ 0
Colombia [Member]
Income Tax Examination [Line Items]
Unpaid equity tax liability	$ 0			$ 0		$ 0
Tax Year 2015 [Member] | Colombia [Member]
Income Tax Examination [Line Items]
Equity tax rate (in hundredths)				1.15%
Tax Year 2016 [Member] | Colombia [Member]
Income Tax Examination [Line Items]
Equity tax rate (in hundredths)				1.00%
Tax Year 2017 [Member] | Colombia [Member]
Income Tax Examination [Line Items]
Equity tax rate (in hundredths)				0.40%

Contingencies (Details)

Contingencies (Details) $ in Millions	Apr. 30, 2015bbl	Sep. 30, 2015USD ($)hydrocarbon_accumulationbbl	Dec. 31, 2014USD ($)	Dec. 31, 2013bbl	Mar. 31, 2015USD ($)
Loss Contingencies [Line Items]
Number of separate hydrocarbon accumulations | hydrocarbon_accumulation		2
Promissory notes provided as collateral for letters of credit		$ 75.7	$ 86.3
Pending Litigation Moqueta Discovery [Member]
Loss Contingencies [Line Items]
Threshold by which additional royalty due (barrels) | bbl		5,000,000
Total cumulative production of oil field (barrels) | bbl	5,000,000
Contingent consideration liability		$ 66.3
Related interest costs					$ 23.6
Royalty agreement basis spread on variable rate		4.00%
Contested interest rate (percent)		29.00%
Related interest		$ 5.7
Pending Litigation Royalty, Transportation and Related Costs [Member]
Loss Contingencies [Line Items]
Contingent consideration liability		43.6
Pending Litigation Escopetrol [Member]
Loss Contingencies [Line Items]
Contingent consideration liability		$ 2.4	$ 2.4
Loss in period in barrels of oil | bbl				44,025

Financial Instruments, Fair V41

Financial Instruments, Fair Value Measurements, Credit Risk and Foreign Exchange Risk - Fair Value of the Foreign Currency Derivatives, Contingent Consideration and the Contingent Liability (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Trading securities	$ 7,016	$ 7,586
Foreign currency derivative liability	0	3,057
Contingent consideration liability	1,061	1,061
Total	$ 1,061	$ 4,118

Financial Instruments, Fair V42

Financial Instruments, Fair Value Measurements, Credit Risk and Foreign Exchange Risk - Gains Recognized in the Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Fair Value Disclosures [Abstract]
Trading securities loss	$ 2,670	$ 2,540	$ 570	$ 2,201
Foreign currency derivatives loss (gain)	0	250	692	(4,424)
Total	$ 2,670	$ 2,790	$ 1,262	$ (2,223)

Financial Instruments, Fair V43

Financial Instruments, Fair Value Measurements, Credit Risk and Foreign Exchange Risk - Narrative (Details) - USD ($) $ in Thousands	Oct. 08, 2012	Sep. 30, 2015	Sep. 30, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign exchange losses, Colombian peso to U.S. dollar		$ 24
Colombia [Member] | Sales Revenue, Segment [Member] | Geographic Concentration Risk [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Concentration risk, percentage		97.00%	95.00%
Block-Brazil [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Participating interest percentage oil and gas property, remaining percentage	30.00%

Severance Costs - Costs by Segm

Severance Costs - Costs by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Restructuring Cost and Reserve [Line Items]
Severance expenses	$ 461	$ 0	$ 6,827	$ 0
Colombia [Member]
Restructuring Cost and Reserve [Line Items]
Severance expenses	0		1,237
Peru [Member]
Restructuring Cost and Reserve [Line Items]
Severance expenses	439		1,863
Brazil [Member]
Restructuring Cost and Reserve [Line Items]
Severance expenses	0		109
All Other [Member]
Restructuring Cost and Reserve [Line Items]
Severance expenses	$ 22		$ 3,618

Severance Costs - Change in Sev

Severance Costs - Change in Severance Cost Liability (Details) - Employee Severance [Member] $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Restructuring Reserve [Roll Forward]
Balance, beginning of period	$ 0
Liability incurred	6,827
Settlements	(6,827)
Balance, end of period	$ 0

Credit Facility - Narrative (De

Credit Facility - Narrative (Details)	9 Months Ended
	Sep. 30, 2015USD ($)Subsidiary
LIBOR [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.00%
Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 200,000,000
Line of Credit Facility, Maximum Borrowing Capacity	$ 500,000,000
Line of Credit, Borrowing Base, Number of Subsidiaries | Subsidiary	2
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.75%
Line of Credit [Member] | LIBOR [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.00%
Line of Credit [Member] | Alternate Base Rate [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Line of Credit [Member] | Alternate Base Rate [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.00%
Line of Credit [Member] | Letter of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 100,000,000
Line of Credit, Credit Participation Fee, Percent	0.25%