Kosmos Energy (KOS) 10-Q 4 Nov 19 2019 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2019	Nov. 01, 2019
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2019
Document Transition Report	false
Entity File Number	001-35167
Entity Registrant Name	Kosmos Energy Ltd.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	98-0686001
Entity Address, Address Line One	8176 Park Lane
Entity Address, City or Town	Dallas,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75231
Title of 12(b) Security	Common Stock $0.01 par value
Trading Symbol	KOS
Security Exchange Name	NYSE
City Area Code	214
Local Phone Number	445 9600
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		401,516,098
Entity Central Index Key	0001509991
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false
Current Fiscal Year End Date	--12-31

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 203,646	$ 173,515
Restricted cash	7,745	4,527
Receivables:
Joint interest billings, net	54,409	64,572
Oil sales	54,612	48,164
Related party	0	5,580
Other	20,016	21,690
Inventories	140,218	84,827
Prepaid expenses and other	47,315	68,040
Derivatives	22,067	38,785
Total current assets	550,028	509,700
Property and equipment:
Oil and gas properties, net	3,780,989	3,444,864
Other property, net	18,047	14,837
Property and equipment, net	3,799,036	3,459,701
Other assets:
Equity method investment	0	51,896
Restricted cash	3,667	7,574
Long-term receivables	36,957	19,002
Deferred financing costs, net of accumulated amortization of $14,027 and $12,065 at September 30, 2019 and December 31, 2018, respectively	6,975	8,937
Deferred tax assets	37,838	14,004
Derivatives	10,535	14,312
Other	23,223	3,063
Total assets	4,468,259	4,088,189
Current liabilities:
Accounts payable	171,495	176,540
Accrued liabilities	292,419	195,596
Derivatives	8,461	12,172
Total current liabilities	472,375	384,308
Long-term liabilities:
Long-term debt, net	2,106,202	2,120,547
Derivatives	2,699	10,181
Asset retirement obligations	284,526	145,336
Deferred tax liabilities	678,808	477,179
Other long-term liabilities	32,619	9,160
Total long-term liabilities	3,104,854	2,762,403
Stockholders’ equity:
Preference shares, $0.01 par value; 200,000,000 authorized shares; zero issued at September 30, 2019 and December 31, 2018	0	0
Common stock, $0.01 par value; 2,000,000,000 authorized shares; 445,757,319 and 442,914,675 issued at September 30, 2019 and December 31, 2018, respectively	4,458	4,429
Additional paid-in capital	2,310,776	2,341,249
Accumulated deficit	(1,187,197)	(1,167,193)
Treasury stock, at cost, 44,263,269 and 44,263,269 shares at September 30, 2019 and December 31, 2018, respectively	(237,007)	(237,007)
Total stockholders’ equity	891,030	941,478
Total liabilities and stockholders’ equity	$ 4,468,259	$ 4,088,189

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Deferred financing costs, accumulated amortization	$ 14,027	$ 12,065
Preference shares, par value (in dollars per share)	$ 0.01	$ 0.01
Preference shares, authorized shares (in shares)	200,000,000	200,000,000
Preference shares, issued shares (in shares)	0	0
Common shares, par value (in dollars per share)	$ 0.01	$ 0.01
Common shares, authorized shares (in shares)	2,000,000,000	2,000,000,000
Common shares, issued shares (in shares)	445,757,319	442,914,675
Treasury stock shares (in shares)	44,263,269	44,263,269

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues and other income:
Oil and gas revenue	$ 357,036			$ 242,833			$ 1,049,759	$ 585,220
Gain on sale of assets	0			7,666			0	7,666
Other income, net	(66)			(280)			(65)	(17)
Total revenues and other income	356,970			250,219			1,049,694	592,869
Costs and expenses:
Oil and gas production	95,540			55,078			266,316	151,661
Facilities insurance modifications, net	12,569			12,334			(5,174)	21,812
Exploration expenses	22,773			148,238			83,022	246,912
General and administrative	24,723			25,963			88,703	65,343
Depletion, depreciation and amortization	146,653			80,041			416,186	208,607
Interest and other financing costs, net	30,721			23,549			125,565	68,113
Derivatives, net	(27,016)			57,357			35,884	236,107
Gain on equity method investments, net	0			(24,841)			0	(59,637)
Other expenses, net	11,472			(12,807)			11,798	(8,164)
Total costs and expenses	317,435			364,912			1,022,300	930,754
Income (loss) before income taxes	39,535			(114,693)			27,394	(337,885)
Income tax expense (benefit)	23,470			11,364			47,398	(58,329)
Net income (loss)	$ 16,065	$ 16,837	$ (52,906)	$ (126,057)	$ (103,273)	$ (50,226)	$ (20,004)	$ (279,556)
Net income (loss) per share:
Basic (in dollars per share)	$ 0.04			$ (0.31)			$ (0.05)	$ (0.70)
Diluted (in dollars per share)	$ 0.04			$ (0.31)			$ (0.05)	$ (0.70)
Weighted average number of shares used to compute net income (loss) per share:
Basic (in shares)	401,466			404,536			401,319	399,026
Diluted (in shares)	410,992			404,536			401,319	399,026
Dividends declared per common stock (in dollars per share)	$ 0.0452	$ 0.0452	$ 0.0452	$ 0			$ 0.1356	$ 0

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Shares	Additional Paid-in Capital	Accumulated Deficit	Treasury Stock
Balance at the beginning (in shares) at Dec. 31, 2017		398,599
Balance at the beginning at Dec. 31, 2017	$ 897,112	$ 3,986	$ 2,014,525	$ (1,073,202)	$ (48,197)
Increase (Decrease) in Shareholders' Equity
Equity-based compensation	8,392		8,392
Restricted stock awards and units (in shares)		6,380
Restricted stock awards and units	0	$ 64	(64)
Purchase of treasury stock / tax withholdings	(11,874)		(11,364)		(510)
Net (loss) income	(50,226)			(50,226)
Balance at the end (in shares) at Mar. 31, 2018		404,979
Balance at the end at Mar. 31, 2018	843,404	$ 4,050	2,011,489	(1,123,428)	(48,707)
Balance at the beginning (in shares) at Dec. 31, 2017		398,599
Balance at the beginning at Dec. 31, 2017	897,112	$ 3,986	2,014,525	(1,073,202)	(48,197)
Increase (Decrease) in Shareholders' Equity
Net (loss) income	(279,556)
Balance at the end (in shares) at Sep. 30, 2018		442,856
Balance at the end at Sep. 30, 2018	934,933	$ 4,429	2,331,969	(1,352,758)	(48,707)
Balance at the beginning (in shares) at Mar. 31, 2018		404,979
Balance at the beginning at Mar. 31, 2018	843,404	$ 4,050	2,011,489	(1,123,428)	(48,707)
Increase (Decrease) in Shareholders' Equity
Equity-based compensation	9,821		9,821
Restricted stock awards and units (in shares)		2,578
Restricted stock awards and units	0	$ 26	(26)
Purchase of treasury stock / tax withholdings	(5,821)		(5,821)
Net (loss) income	(103,273)			(103,273)
Balance at the end (in shares) at Jun. 30, 2018		407,557
Balance at the end at Jun. 30, 2018	744,131	$ 4,076	2,015,463	(1,226,701)	(48,707)
Increase (Decrease) in Shareholders' Equity
Acquisition of oil and gas properties (in shares)		34,994
Acquisition of oil and gas properties	307,944	$ 350	307,594
Equity-based compensation	8,915		8,915
Restricted stock awards and units (in shares)		305
Restricted stock awards and units	0	$ 3	(3)
Net (loss) income	(126,057)			(126,057)
Balance at the end (in shares) at Sep. 30, 2018		442,856
Balance at the end at Sep. 30, 2018	934,933	$ 4,429	2,331,969	(1,352,758)	(48,707)
Balance at the beginning (in shares) at Dec. 31, 2018		442,915
Balance at the beginning at Dec. 31, 2018	941,478	$ 4,429	2,341,249	(1,167,193)	(237,007)
Increase (Decrease) in Shareholders' Equity
Dividends ($0.0452 per share)	(18,744)		(18,744)
Equity-based compensation	8,744		8,744
Restricted stock awards and units (in shares)		2,610
Restricted stock awards and units	0	$ 26	(26)
Purchase of treasury stock / tax withholdings	(1,979)		(1,979)
Net (loss) income	(52,906)			(52,906)
Balance at the end (in shares) at Mar. 31, 2019		445,525
Balance at the end at Mar. 31, 2019	876,593	$ 4,455	2,329,244	(1,220,099)	(237,007)
Balance at the beginning (in shares) at Dec. 31, 2018		442,915
Balance at the beginning at Dec. 31, 2018	941,478	$ 4,429	2,341,249	(1,167,193)	(237,007)
Increase (Decrease) in Shareholders' Equity
Net (loss) income	(20,004)
Balance at the end (in shares) at Sep. 30, 2019		445,757
Balance at the end at Sep. 30, 2019	891,030	$ 4,458	2,310,776	(1,187,197)	(237,007)
Balance at the beginning (in shares) at Mar. 31, 2019		445,525
Balance at the beginning at Mar. 31, 2019	876,593	$ 4,455	2,329,244	(1,220,099)	(237,007)
Increase (Decrease) in Shareholders' Equity
Dividends ($0.0452 per share)	(18,740)		(18,740)
Equity-based compensation	9,525		9,525
Restricted stock awards and units (in shares)		113
Restricted stock awards and units	0	$ 1	(1)
Purchase of treasury stock / tax withholdings	(4)		(4)
Net (loss) income	16,837			16,837
Balance at the end (in shares) at Jun. 30, 2019		445,638
Balance at the end at Jun. 30, 2019	884,211	$ 4,456	2,320,024	(1,203,262)	(237,007)
Increase (Decrease) in Shareholders' Equity
Dividends ($0.0452 per share)	(18,753)		(18,753)
Equity-based compensation	9,507		9,507
Restricted stock awards and units (in shares)		119
Restricted stock awards and units	0	$ 2	(2)
Net (loss) income	16,065			16,065
Balance at the end (in shares) at Sep. 30, 2019		445,757
Balance at the end at Sep. 30, 2019	$ 891,030	$ 4,458	$ 2,310,776	$ (1,187,197)	$ (237,007)

CONSOLIDATED STATEMENTS OF SH_2

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended				9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Stockholders' Equity [Abstract]
Dividends declared per common stock (in dollars per share)	$ 0.0452	$ 0.0452	$ 0.0452	$ 0	$ 0.1356	$ 0

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Operating activities
Net loss	$ (20,004)	$ (279,556)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depletion, depreciation and amortization	423,160	215,676
Deferred income taxes	(69,840)	(84,095)
Unsuccessful well costs and leasehold impairments	7,361	114,948
Change in fair value of derivatives	34,003	232,057
Cash settlements on derivatives, net (including $(27.0) million and $(107.3) million on commodity hedges during 2019 and 2018)	(24,701)	(102,705)
Equity-based compensation	27,382	25,975
Gain on sale of assets	0	(7,666)
Loss on extinguishment of debt	24,794	4,324
Distributions in excess of equity in earnings	0	5,235
Other	9,600	1,237
Changes in assets and liabilities:
Decrease in receivables	12,886	59,318
(Increase) decrease in inventories	(51,943)	3,978
(Increase) decrease in prepaid expenses and other	23,512	(9,732)
Decrease in accounts payable	(61,909)	(15,178)
Increase (decrease) in accrued liabilities	65,975	(73,569)
Net cash provided by operating activities	400,276	90,247
Investing activities
Oil and gas assets	(240,642)	(149,305)
Other property	(8,291)	(3,560)
Acquisition of oil and gas properties, net of cash acquired	0	(961,764)
Return of investment from KTIPI	0	142,628
Proceeds on sale of assets	0	13,703
Notes receivable from partners	(19,565)	0
Net cash used in investing activities	(268,498)	(958,298)
Financing activities
Borrowings under long-term debt	175,000	1,000,000
Payments on long-term debt	(325,000)	(175,000)
Net proceeds from issuance of senior notes	641,875	0
Redemption of senior secured notes	(535,338)	0
Purchase of treasury stock / tax withholdings	(1,983)	(17,695)
Dividends	(54,447)	0
Deferred financing costs	(2,443)	(36,745)
Net cash provided by (used in) financing activities	(102,336)	770,560
Net increase (decrease) in cash, cash equivalents and restricted cash	29,442	(97,491)
Cash, cash equivalents and restricted cash at beginning of period	185,616	304,986
Cash, cash equivalents and restricted cash at end of period	215,058	207,495
Cash paid for:
Interest, net of capitalized interest	78,691	86,981
Income taxes	27,768	25,601
Non-cash activity:
Common stock issued for acquisition of oil and gas properties	$ 0	$ 307,944

CONSOLIDATED STATEMENTS OF CA_2

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Statement of Cash Flows [Abstract]
Cash settlements on derivatives, net (commodity hedges)	$ (27)	$ (107.3)

Organization

Organization	9 Months Ended
	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Kosmos Energy Ltd. changed its jurisdiction of incorporation from Bermuda to the State of Delaware, in the United States of America, (the "Redomestication") in December 2018. As a holding company, Kosmos Energy Ltd.’s management operations are conducted through a wholly-owned subsidiary, Kosmos Energy, LLC. The terms “Kosmos,” the “Company,” “we,” “us,” “our,” “ours,” and similar terms refer to Kosmos Energy Ltd. and its wholly-owned subsidiaries, unless the context indicates otherwise. Kosmos is a full-cycle deepwater independent oil and gas exploration and production company focused along the Atlantic Margins. Our key assets include production offshore Ghana, Equatorial Guinea and U.S. Gulf of Mexico, as well as a world-class gas development offshore Mauritania and Senegal. We also maintain a sustainable exploration program balanced between proven basin infrastructure-led exploration (Equatorial Guinea and U.S. Gulf of Mexico), emerging basins (Mauritania, Senegal and Suriname) and frontier basins (Cote d'Ivoire, Namibia, Sao Tome and Principe, and South Africa). Kosmos is listed on the New York Stock Exchange and London Stock Exchange and is traded under the ticker symbol KOS. Kosmos is engaged in a single line of business, which is the exploration, development, and production of oil and natural gas. Substantially all of our long-lived assets and all of our product sales are related to operations in four geographic areas: Ghana, Equatorial Guinea, Mauritania/Senegal and U.S. Gulf of Mexico. In addition, we have exploration activities in other countries in the Atlantic Margins.

Accounting Policies

Accounting Policies	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Accounting Policies	Accounting Policies General The interim consolidated financial statements included in this report are unaudited and, in the opinion of management, include all adjustments of a normal recurring nature necessary for a fair presentation of the results for the interim periods. The results of the interim periods shown in this report are not necessarily indicative of the final results to be expected for the full year. The consolidated financial statements were prepared in accordance with the requirements of the Securities and Exchange Commission (“SEC”) for interim reporting. As permitted under those rules, certain notes or other financial information that are normally required by Generally Accepted Accounting Principles in the United States of America (“GAAP”) have been condensed or omitted from these interim consolidated financial statements. These consolidated financial statements and the accompanying notes should be read in conjunction with our audited consolidated financial statements for the year ended December 31, 2018 , included in our annual report on Form 10-K. Reclassifications Certain prior period amounts have been reclassified to conform with the current presentation. Such reclassifications had no significant impact on our reported net income (loss) , current assets, total assets, current liabilities, total liabilities, stockholders’ equity or cash flows. Additionally, as a result of our outstanding shares in KTIPI being transferred for an undivided interest in the Ceiba Field and Okume Complex (effective January 1, 2019), our previously reported equity method investment in KTIPI has been allocated to the respective assets and liabilities on a relative fair value basis. See Note 7 — Equity Method Investments for additional information. Cash, Cash Equivalents and Restricted Cash September 30, December 31, (In thousands) Cash and cash equivalents $ 203,646 $ 173,515 Restricted cash - current 7,745 4,527 Restricted cash - long-term 3,667 7,574 Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows $ 215,058 $ 185,616 Cash and cash equivalents include demand deposits and funds invested in highly liquid instruments with original maturities of three months or less at the date of purchase. In accordance with certain of our petroleum contracts, we have posted letters of credit related to performance guarantees for our minimum work obligations. Certain of these letters of credit are cash collateralized in accounts held by us and as such are classified as restricted cash. Upon completion of the minimum work obligations and/or entering into the next phase of the respective petroleum contract, the requirement to post the existing letters of credit will be satisfied and the cash collateral will be released. However, additional letters of credit may be required should we choose to move into the next phase of certain of our petroleum contracts. Inventories Inventories consisted of $123.6 million and $83.4 million of materials and supplies and $16.6 million and $1.4 million of hydrocarbons as of September 30, 2019 and December 31, 2018 , respectively. The Company’s materials and supplies inventory primarily consists of casing and wellheads and is stated at the lower of cost, using the weighted average cost method, or net realizable value. Hydrocarbon inventory is carried at the lower of cost, using the weighted average cost method, or net realizable value. Hydrocarbon inventory costs include expenditures and other charges incurred in bringing the inventory to its existing condition. Selling expenses and general and administrative expenses are reported as period costs and excluded from inventory costs. Leases (Policy applicable beginning January 1, 2019) In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842).” ASU 2016-02 was issued to increase transparency and comparability across organizations by recognizing substantially all leases on the balance sheet through the concept of right-of-use lease assets and liabilities. Under prior accounting guidance, lessees did not recognize lease assets or liabilities for leases classified as operating leases. The ASU was effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years with early adoption permitted. In July 2018, the FASB issued ASU 2018-11, which added a transition option permitting entities to apply the provisions of the new standard at its adoption date instead of the earliest comparative period presented in the consolidated financial statements. Under this transition option, comparative reporting would not be required, and the provisions of the standard would be applied prospectively to leases in effect at the date of adoption. The Company adopted the guidance prospectively during the first quarter of 2019. As part of our adoption, we elected not to reassess historical lease classification, recognize short-term leases on our balance sheet, nor separate lease and non-lease components for our real estate leases. The adoption and implementation of this ASU resulted in a $21.7 million increase in assets and liabilities related to our leasing activities, which primarily consists of office leases. Our adoption of ASU 2016-02 did not impact retained earnings or other components of equity as of December 31, 2018. We account for leases in accordance with ASC Topic 842, Leases, (“ASC 842”). We determine if an arrangement is a lease at contract inception. A lease exists when a contract conveys to the customer the right to control the use of identified property, plant, or equipment for a period of time in exchange for consideration. The definition of a lease embodies two conditions: (1) there is an identified asset in the contract that is land or a depreciable asset (i.e., property, plant, and equipment), and (2) the customer has the right to control the use of the identified asset. In the normal course of business, the Company enters into various lease agreements for real estate and equipment related to its exploration, development and production activities that are currently accounted for as operating leases. Operating leases are included in Other assets, Accrued liabilities, and Other long-term liabilities on our consolidated balance sheets. The lease liabilities are initially and subsequently measured at the present value of the unpaid lease payments at the lease commencement date. Key estimates and judgments include how we determined: (1) the discount rate we use to discount the unpaid lease payments to present value; (2) lease term; and (3) lease payments. 1. ASC 842 requires a lessee to discount its unpaid lease payments using the interest rate implicit in the lease or, if that rate cannot be readily determined, its incremental borrowing rate. As most of our leases where we are the lessee do not provide an implicit rate, we use our incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. Our incremental borrowing rate for a lease is the rate of interest we would have to pay on a collateralized basis to borrow an amount equal to the lease payments under similar terms. 2. The lease term for all of our leases includes the non-cancellable period of the lease plus any additional periods covered by either an option to extend (or not to terminate) the lease that we are reasonably certain to exercise, or an option to extend (or not to terminate) the lease controlled by the lessor. 3. Lease payments included in the measurement of the lease asset or liability comprise the following: fixed payments (including in-substance fixed payments), variable payments that depend on index or rate, and the exercise price of a lessee option to purchase the underlying asset if we are reasonably certain to exercise. Amounts expected to be payable under residual value guarantee are also lease payments included in the measurement of the lease liability. The Right-of-use ("ROU") asset is initially measured at cost, which comprises the initial amount of the lease liability adjusted for lease payments made at or before the lease commencement date, plus any initial direct costs incurred less any lease incentives received. For operating leases, the ROU asset is subsequently measured throughout the lease term at the carrying amount of the lease liability, plus initial direct costs, plus (minus) any prepaid (accrued) lease payments, less the unamortized balance of lease incentives received. Lease expense for lease payments is recognized on a straight-line basis over the lease term. We monitor for events or changes in circumstances that require a reassessment of a lease. When a reassessment results in the re-measurement of a lease liability, a corresponding adjustment is made to the carrying amount of the corresponding ROU asset unless doing so would reduce the carrying amount of the ROU asset to an amount less than zero. In that case, the amount of the adjustment that would result in a negative ROU asset balance is recorded in profit or loss. We have lease agreements which include lease and non-lease components. We have elected to combine lease and non-lease components for all lease contracts. We have elected not to recognize ROU assets and lease liabilities for all short-term leases that have a lease term of 12 months or less. We recognize the lease payments associated with our short-term leases as an expense on a straight-line basis over the lease term. We adopted ASU 2016-02 using a modified retrospective transition approach as of the effective date as permitted by the amendments in ASU 2018-11, which provides an alternative modified retrospective transition method. As a result, we were not required to adjust our comparative period financial information for effects of the standard or make the new required lease disclosures for periods before the date of adoption (i.e. January 1, 2019). We have elected to adopt the package of transition practical expedients and, therefore, have not reassessed (1) whether existing or expired contracts contain a lease, (2) lease classification for existing or expired leases or (3) the accounting for initial direct costs that were previously capitalized. We did not elect the practical expedient to use hindsight for leases existing at the adoption date. Revenue Recognition We recognize revenues on the volumes of hydrocarbons sold to a purchaser. The volumes sold may be more or less than the volumes to which we are entitled based on our ownership interest in the property. These differences result in a condition known in the industry as a production imbalance. A receivable or liability is recognized only to the extent that we have an imbalance on a specific property greater than the expected remaining proved reserves on such property. As of September 30, 2019 and December 31, 2018 , we had no oil and gas imbalances recorded in our consolidated financial statements. Our oil and gas revenues are recognized when hydrocarbons have been sold to a purchaser at a fixed or determinable price, title has transferred and collection is probable. Certain revenues are based on provisional price contracts which contain an embedded derivative that is required to be separated from the host contract for accounting purposes. The host contract is the receivable from oil sales at the spot price on the date of sale. The embedded derivative, which is not designated as a hedge, is marked to market through oil and gas revenue each period until the final settlement occurs, which generally is limited to the month after the sale. Oil and gas revenue is composed of the following: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (In thousands) Revenues from contract with customer - Equatorial Guinea $ 54,894 $ — $ 207,173 $ — Revenues from contract with customer - Ghana 173,613 215,581 502,413 557,459 Revenues from contract with customers - U.S. Gulf of Mexico 123,861 24,177 338,292 24,177 Provisional oil sales contracts 4,668 3,075 1,881 3,584 Oil and gas revenue $ 357,036 $ 242,833 $ 1,049,759 $ 585,220 Concentration of Credit Risk Our revenue can be materially affected by current economic conditions and the price of oil. However, based on the current demand for crude oil and the fact that alternative purchasers are readily available, we believe that the loss of our marketing agent and/or any of the purchasers identified by our marketing agent would not have a long‑term material adverse effect on our financial position or results of international operations. For our U.S. Gulf of Mexico operations, crude oil and natural gas are transported to customers using third-party pipelines. For the three months ended September 30, 2019 and 2018 , revenue from Phillips 66 Company made up approximately 21% and 6% , respectively, and revenue from Shell Trading (US) Company made up approximately 11% and 3% , respectively, of our total consolidated revenue and was included in our U.S. Gulf of Mexico segment. For the nine months ended September 30, 2019 and 2018 , revenue from Phillips 66 Company made up approximately 22% and 3% , respectively, and revenue from Shell Trading (US) Company made up approximately 9% and 1% , respectively, of our total consolidated revenue and was included in our U.S. Gulf of Mexico segment. Recent Accounting Standards

Acquisitions and Divestitures

Acquisitions and Divestitures	9 Months Ended
	Sep. 30, 2019
Business Combinations [Abstract]
Acquisitions and Divestitures	Acquisitions and Divestitures 2019 Transactions During the first quarter of 2019, we entered into a petroleum contract covering offshore Marine XXI block with the Republic of the Congo, subject to customary governmental approvals. Upon approval, we will hold an 85% participating interest and will be the operator. The Congolese national oil company, SNPC, has a 15% carried interest during the exploration period. Should a commercial discovery be made, SNPC's 15% carried interest will convert to a participating interest of at least 15% . The petroleum contract covers approximately 2,350 square kilometers, with a first exploration period of four years and includes a work program to acquire and interpret 2,200 square kilometers of 3D seismic. There are two optional exploration phases, each for a period of three years , which are subject to additional work program commitments. During the first quarter of 2019, Kosmos farmed-in to 18 BP-owned blocks in the Garden Banks area of the deepwater U.S. Gulf of Mexico. In addition, Kosmos can earn an interest in three BP blocks in other areas of the deepwater U.S. Gulf of Mexico. Kosmos is the designated operator. During the first quarter of 2019, Kosmos executed a farm-in agreement with Chevron covering the right to earn an interest in a deepwater block in the U.S. Gulf of Mexico. Kosmos has been designated operator. During the first quarter of 2019, Kosmos participated in the U.S. Gulf of Mexico Federal Lease Sale 252 and was awarded nine deepwater blocks. During the third quarter of 2019, Kosmos participated in the U.S. Gulf of Mexico Federal Lease Sale 253 and was awarded four deepwater blocks. In March 2019, we completed an agreement to acquire Ophir's remaining interest in Block EG-24, offshore Equatorial Guinea, which increased our participating interest to 80% and named Kosmos as operator. The Equatorial Guinean national oil company, GEPetrol, has a 20% carried interest during the exploration period. Should a commercial discovery be made, GEPetrol's 20% carried interest will convert to a 20% participating interest. In May 2019, we entered into a farm-out agreement with Shell Sao Tome and Principe B.V. to farm-out a 20% participating interest in Block 6 and a 30% participating interest in Block 11, offshore Sao Tome and Principe, subject to customary governmental approvals, resulting in our participating interests in Blocks 6 and 11 being 25% and 35% , respectively. In September 2019, we completed a farm-in agreement with OK Energy to acquire a 45% non-operated interest in the Northern Cape Ultra Deep block offshore the Republic of South Africa. The petroleum contract covers approximately 6,930 square kilometers at water depths ranging from 2,500 to 3,100 meters and has an initial exploration phase of two years . 2018 Transactions In March 2018, as part of our alliance with BP, we entered into petroleum contracts covering Blocks 10 and 13 with the Democratic Republic of Sao Tome and Principe and BP. We have a 35% participating interest in the blocks and the operator, BP, holds a 50% participating interest. The national petroleum agency, ANP-STP, has a 15% carried interest in the blocks through exploration. The petroleum contracts cover approximately 13,600 square kilometers, with a first exploration period of four years from the effective date (March 2018). The exploration periods can be extended an additional four years at our election subject to fulfilling specific work obligations. The first exploration period work programs include a 13,500 square kilometer 3D seismic acquisition across the two blocks. In June 2018, we completed a farm-in agreement with a subsidiary of Ophir for Block EG-24, offshore Equatorial Guinea, whereby we acquired our initial non-operated participating interest of 40% . As part of the agreement, we reimbursed a portion of Ophir's previously incurred exploration costs and agreed to carry Ophir's share of the future costs. The petroleum contract covers approximately 3,500 square kilometers, with a first exploration period of three years from the effective date (March 2018), which can be extended up to four additional years at our election subject to fulfilling specific work obligations. The first exploration period work program includes a 3,000 square kilometer 3D seismic acquisition requirement which was completed in November 2018. The Equatorial Guinean national oil company, GEPetrol, has a 20% carried interest during the exploration period. Should a commercial discovery be made, GEPetrol's 20% carried interest will convert to a 20% participating interest. In August 2018, we closed a farm-out agreement with Trident, whereby they acquired a 40% participating interest in blocks EG-21, S, and W, offshore Equatorial Guinea, resulting in a $7.7 million gain. After giving effect to the farm-out agreement, we hold a 40% participating interest and are the operator in all three blocks. The Equatorial Guinean national oil company, GEPetrol, has a 20% carried participating interest during the exploration period. Should a commercial discovery be made, GEPetrol's 20% carried participating interest will convert to a 20% participating interest. The petroleum contracts cover approximately 6,000 square kilometers, with a first exploration period of five years from the effective date (March 2018). The first exploration period consists of two sub-periods of three and two years , respectively. The first exploration sub-period work program includes a 6,000 square kilometer 3D seismic acquisition requirement across the three blocks, which was completed in 2018. In September 2018, we completed the acquisition of DGE, a deepwater company operating in the U.S. Gulf of Mexico, from First Reserve Corporation and other shareholders for a total consideration of $1.275 billion , comprised of $952.6 million in cash, $307.9 million in Kosmos common stock, and $14.9 million of transaction related costs. We funded the cash portion of the purchase price using cash on hand and drawings under our existing credit facilities. The DGE acquisition was accounted for as an asset acquisition. In October 2018, Kosmos entered into a strategic exploration alliance with Shell to jointly explore in Southern West Africa. Initially the alliance will focus on Namibia where Kosmos has completed a farm-in to Shell's acreage in PEL 39, and Sao Tome and Principe. As part of the alliance, our two companies intend to jointly evaluate opportunities in adjacent geographies. This alliance is consistent with Kosmos’ strategy of partnering with supermajors to leverage complementary skill sets. Shell has deep expertise in carbonate plays, while Kosmos brings significant knowledge of the Cretaceous in West Africa. Furthermore, by

Joint Interest Billings, Relate

Joint Interest Billings, Related Party Receivables and Notes Receivables	9 Months Ended
	Sep. 30, 2019
Joint Interest Billings
Joint Interest Billings, Related Party Receivables and Notes Receivables	Joint Interest Billings, Related Party Receivables and Notes Receivables Joint Interest Billings The Company’s joint interest billings generally consist of receivables from partners with interests in common oil and gas properties operated by the Company for shared costs. Joint interest billings are classified on the face of the consolidated balance sheets as current and long-term receivables based on when collection is expected to occur. In 2014, GNPC notified us and our block partners of its request for the contractor group to pay GNPC’s 5% share of the Tweneboa, Enyenra and Ntomme (“TEN”) development costs. The block partners are being reimbursed for such costs plus interest out of a portion of GNPC’s TEN production revenues. As of September 30, 2019 and December 31, 2018 , the current portions of the joint interest billing receivables due from GNPC for the TEN fields development costs were $14.0 million and $14.0 million , respectively, and the long-term portions were $17.2 million and $14.0 million , respectively. Related Party Receivables The Company's related party receivables consists primarily of receivables from Trident which, until January 2019, we shared a 50% interest in KTIPI. As of December 31, 2018 the balance due from Trident consisted of $ 5.6 million related to joint interest billings for the exploration blocks and Kosmos' support of KTIPI operations. Subsequent to the unwind of KTIPI, Trident is no longer considered a related party. Notes Receivables In February 2019, Kosmos and BP signed Carry Advance Agreements with the national oil companies of Mauritania and Senegal which obligate us separately to finance the respective national oil company’s share of certain development costs incurred through first gas production for Greater Tortue Ahmeyim Phase 1, currently projected in 2022. Kosmos’ share for the two agreements combined is up to $239.7 million , which is to be repaid with interest through the national oil companies’ share of future revenues. As of September 30, 2019 , the balance due from the national oil companies was $19.8 million , which is classified as Long-term receivables in our consolidated balance sheets.

Property and Equipment

Property and Equipment	9 Months Ended
	Sep. 30, 2019
Property, Plant and Equipment [Abstract]
Property and Equipment	Property and Equipment Property and equipment is stated at cost and consisted of the following: September 30, December 31, (In thousands) Oil and gas properties: Proved properties $ 4,827,304 $ 4,236,489 Unproved properties 898,855 759,472 Total oil and gas properties 5,726,159 4,995,961 Accumulated depletion (1,945,170 ) (1,551,097 ) Oil and gas properties, net 3,780,989 3,444,864 Other property 59,515 51,987 Accumulated depreciation (41,468 ) (37,150 ) Other property, net 18,047 14,837 Property and equipment, net $ 3,799,036 $ 3,459,701 We recorded depletion expense of $139.1 million and $76.8 million for the three months ended September 30, 2019 and 2018 , respectively, and $394.1 million and $199.7 million for the nine months ended September 30, 2019 and 2018

Suspended Well Costs

Suspended Well Costs	9 Months Ended
	Sep. 30, 2019
Oil and Gas Exploration and Production Industries Disclosures [Abstract]
Suspended Well Costs	Suspended Well Costs The following table reflects the Company’s capitalized exploratory well costs on drilled wells as of and during the nine months ended September 30, 2019 . The table excludes $1.4 million in costs that were capitalized and subsequently expensed during the same period. September 30, (In thousands) Beginning balance $ 367,665 Additions to capitalized exploratory well costs pending the determination of proved reserves 55,244 Reclassification due to determination of proved reserves (10,711 ) Capitalized exploratory well costs charged to expense — Ending balance $ 412,198 The following table provides an aging of capitalized exploratory well costs based on the date drilling was completed and the number of projects for which exploratory well costs have been capitalized for more than one year since the completion of drilling: September 30, 2019 December 31, 2018 (In thousands, except well counts) Exploratory well costs capitalized for a period of one year or less $ — $ — Exploratory well costs capitalized for a period of one to two years 77,995 299,253 Exploratory well costs capitalized for a period of three years or greater 334,203 68,412 Ending balance $ 412,198 $ 367,665 Number of projects that have exploratory well costs that have been capitalized for a period greater than one year 3 3 As of September 30, 2019 , the projects with exploratory well costs capitalized for more than one year since the completion of drilling are related to the Greater Tortue Ahmeyim Unit, which crosses the Mauritania and Senegal maritime border, the Bir Allah discovery (formerly known as the Marsouin discovery) in Block C8 offshore Mauritania, and the Yakaar and Teranga discoveries in the Cayar Offshore Profond block offshore Senegal. Greater Tortue Ahmeyim Unit — In May 2015, we completed the Tortue-1 exploration well in Block C8 offshore Mauritania, which encountered hydrocarbon pay. Three additional wells have been drilled in the unit development area of the Greater Tortue Ahmeyim field, Ahmeyim-2 in Mauritania and Guembeul-1 and Greater Tortue Ahmeyim-1 in Senegal. We completed a drill stem test on the Tortue‑1 well in August 2017, which confirmed the production capabilities of the Greater Tortue Ahmeyim Unit. In December 2018, we made a final investment decision to develop Phase 1 of the Greater Tortue Ahmeyim Unit, with first gas production currently estimated in 2022. Bir Allah Discovery — In November 2015, we completed the Marsouin-1 exploration well in the northern part of Block C8 offshore Mauritania, which encountered hydrocarbon pay. Following additional evaluation, a decision regarding commerciality is expected to be made. During the fourth quarter of 2019, we completed the nearby Orca-1 exploration well which encountered hydrocarbon pay. Following additional evaluation, a decision regarding commerciality is expected to be made.

Equity Method Investments

Equity Method Investments	9 Months Ended
	Sep. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Equity Method Investments Equatorial Guinea As part of our acquisition of KTIPI in 2017, a corporate joint venture entity in which we owned a 50% interest until January 2019, we acquired an indirect participating interest in Block G offshore Equatorial Guinea. The objective of this transaction was to acquire the Ceiba Field and Okume Complex with the intent to optimize production and increase reserves. Below is a summary of financial information for KTIPI presented on a 100% basis for 2018. The financial information for 2019 is presented as part of our consolidated financial statements based on our direct 40.375% ownership in the Ceiba Field and Okume Complex. December 31, 2018 (In thousands) Assets Total current assets $ 149,950 Property and equipment, net 271,627 Other assets 21 Total assets $ 421,598 Liabilities and stockholders' equity Total current liabilities $ 226,311 Total long-term liabilities 536,178 Shareholders' equity: Total shareholders' equity (340,891 ) Total liabilities and shareholders' equity $ 421,598 Three Months Ended Nine Months Ended (In thousands) Revenues and other income: Oil and gas revenue $ 215,408 $ 600,158 Other income (72 ) 44 Total revenues and other income 215,336 600,202 Costs and expenses: Oil and gas production 40,334 115,366 Depletion, depreciation and amortization 33,044 108,996 Other expenses, net (58 ) (211 ) Total costs and expenses 73,320 224,151 Income before income taxes 142,016 376,051 Income tax expense 50,796 134,047 Net income $ 91,220 $ 242,004 Kosmos' share of net income $ 45,610 $ 121,002 Basis difference amortization(1) 20,769 61,365 Equity in earnings - KTIPI $ 24,841 $ 59,637 ______________________________________ (1) The basis difference, which was associated with oil and gas properties and subject to amortization, has been allocated to the Ceiba Field and Okume Complex. We amortized the basis difference using the unit-of-production method. With an effective date of January 1, 2019, our outstanding shares in KTIPI were transferred to Trident in exchange for a 40.375% undivided participating interest in the Ceiba Field and Okume Complex. As a result, our interest in the Ceiba Field and Okume Complex is accounted for under the proportionate consolidation method of accounting going forward. This transaction was accounted for as an asset acquisition. The carrying value of the equity method investment was allocated to the undivided interest acquired and net working capital based on the estimated relative fair value of the acquired assets. The estimated fair value measurements of oil and gas assets acquired and liabilities assumed are based on inputs that are not observable in the market and therefore represent Level 3 inputs. The fair value of oil and gas properties and asset retirement obligations were measured using the discounted cash flow technique of valuation. Significant inputs to the valuation of oil and gas properties include estimates of: (i) reserves, (ii) future operating and development costs, (iii) future commodity prices, (iv) future plugging and abandonment costs, (v) estimated future cash flows, and (vi) a market-based weighted average cost of capital rate. Carrying Value Allocation (in thousands) Assets acquired: Proved oil and gas properties $ 372,144 Unproved oil and gas properties 103,909 Prepaids and other 7,273 Total assets acquired $ 483,326 Liabilities assumed: Asset retirement obligations $ 114,395 Deferred tax liabilities 247,636 Accrued liabilities and other 69,399 Total liabilities assumed $ 431,430 Carrying value: Equity method investment carrying value at December 31, 2018 $ 51,896

Debt

Debt	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Debt	Debt September 30, December 31, (In thousands) Outstanding debt principal balances: Facility $ 1,500,000 $ 1,325,000 Corporate Revolver — 325,000 Senior Notes 650,000 — Senior Secured Notes — 525,000 Total 2,150,000 2,175,000 Unamortized deferred financing costs and discounts(1) (43,798 ) (54,453 ) Long-term debt, net $ 2,106,202 $ 2,120,547 __________________________________ (1) Includes $34.4 million and $40.5 million of unamortized deferred financing costs related to the Facility as of September 30, 2019 and December 31, 2018 , respectively; $9.4 million of unamortized deferred financing costs and discounts related to the Senior Notes as of September 30, 2019 ; and $14.0 million of unamortized deferred financing costs and discounts related to the Senior Secured Notes as of December 31, 2018 , respectively. Facility In February 2018, the Company amended and restated the Facility with a total commitment of $1.5 billion from a number of financial institutions, with additional commitments up to $0.5 billion being available if the existing financial institutions increase their commitments or if commitments from new financial institutions are added. The borrowing base calculation includes value related to the Jubilee, TEN, Ceiba and Okume fields. In March 2019, following the lender's annual redetermination, the available borrowing base under our Facility was limited to the Facility size of $1.7 billion . The Facility supports our oil and gas exploration, appraisal and development programs and corporate activities. As part of the debt refinancing in February 2018, the repayment of borrowings under the existing facility attributable to financial institutions that did not participate in the amended Facility was accounted for as an extinguishment of debt, and $4.1 million of existing unamortized debt issuance costs and deferred interest attributable to those participants was expensed in interest and other financing costs, net in the first quarter of 2018. As of September 30, 2019 , we have $34.4 million of unamortized issuance costs related to the Facility, which will be amortized over the remaining term of the Facility. As of September 30, 2019 , the undrawn availability under the Facility was $100.0 million . The commitments were reduced by $100.0 million to $1.6 billion following the Senior Notes issuance in April 2019. The Facility provides a revolving credit and letter of credit facility. The availability period for the revolving credit facility expires one month prior to the final maturity date. The letter of credit facility expires on the final maturity date. The available facility amount is subject to borrowing base constraints and, beginning on March 31, 2022, outstanding borrowings will be constrained by an amortization schedule. The Facility has a final maturity date of March 31, 2025. As of September 30, 2019 , we had no letters of credit issued under the Facility. We were in compliance with the financial covenants contained in the Facility as of September 30, 2019 (the most recent assessment date). The Facility contains customary cross default provisions. Corporate Revolver In August 2018, we amended and restated the Corporate Revolver from a number of financial institutions, maintaining the borrowing capacity at $400.0 million , extending the maturity date from November 2018 to May 2022 and lowering the margin 100 basis points to 5% . This results in lower commitment fees on the undrawn portion of the total commitments, which is 30% per annum of the respective margin. The Corporate Revolver is available for general corporate purposes and for oil and gas exploration, appraisal and development programs. As of September 30, 2019 , the undrawn availability under the Corporate Revolver was $400.0 million . As of September 30, 2019 , we have $7.0 million of net deferred financing costs related to the Corporate Revolver, which will be amortized over its remaining term. We were in compliance with the financial covenants contained in the Corporate Revolver as of September 30, 2019 (the most recent assessment date). The Corporate Revolver contains customary cross default provisions. Revolving Letter of Credit Facility Our revolving letter of credit facility agreement (“LC Facility”) expired in July 2019 , however, as of September 30, 2019 , there were six outstanding letters of credit totaling $9.4 million under the LC Facility, which will remain outstanding until the respective letters of credit expire. The LC Facility contains customary cross default provisions. In 2019, we issued two letters of credit totaling $20.4 million under a new letter of credit arrangement, which does not currently require cash collateral. 7.875% Senior Secured Notes due 2021 During August 2014, the Company issued $300.0 million of 7.875% Senior Secured Notes due 2021 (the "Senior Secured Notes") and received net proceeds of approximately $292.5 million after deducting discounts, commissions and debt issue costs. The Company used the net proceeds to repay a portion of the outstanding indebtedness under the Facility and for general corporate purposes. During April 2015, we issued an additional $225.0 million of Senior Secured Notes and received net proceeds of $206.8 million after deducting discounts, commissions and other expenses. We used the net proceeds to repay a portion of the outstanding indebtedness under the Facility and for general corporate purposes. The additional $225.0 million of Senior Secured Notes had identical terms to the initial $300.0 million of Senior Secured Notes, other than the date of issue, the initial price, the first interest payment date and the first date from which interest accrued. In April 2019, all of the Senior Secured Notes were redeemed for $543.8 million , including accrued interest and the early redemption premium. The redemption resulted in a $22.9 million loss on extinguishment of debt, which is included in Interest and other financing costs, net on the consolidated statement of operations. 7.125% Senior Notes due 2026 In April 2019, the Company issued $650.0 million of 7.125% Senior Notes (the "Senior Notes") and received net proceeds of approximately $640.0 million after deducting commissions and other expenses. We used the net proceeds to redeem all of the Senior Secured Notes, repay a portion of the outstanding indebtedness under the Corporate Revolver and pay fees and expenses related to the redemption, repayment and the issuance of the Senior Notes. The Senior Notes mature on April 4, 2026. We will pay interest in arrears on the Senior Notes each April 4 and October 4, commencing on October 4, 2019. The Senior Notes are senior, unsecured obligations of Kosmos Energy Ltd. and rank equal in right of payment with all of its existing and future senior indebtedness (including all borrowings under the Corporate Revolver) and rank effectively junior in right of payment to all of its existing and future secured indebtedness (including all borrowings under the Facility). The Senior Notes are guaranteed on a senior, unsecured basis by certain subsidiaries owning the Company's Gulf of Mexico assets, and on a subordinated, unsecured basis by certain subsidiaries that guarantee the Facility. At any time prior to April 4, 2022, and subject to certain conditions, the Company may, on one or more occasions, redeem up to 40% of the original principal amount of the Senior Notes with an amount not to exceed the net cash proceeds of certain equity offerings at a redemption price of 107.1% of the outstanding principal amount of the Senior Notes, together with accrued and unpaid interest and premium, if any, to, but excluding, the date of redemption. Additionally, at any time prior to April 4, 2022 the Company may, on any one or more occasions, redeem all or a part of the Senior Notes at a redemption price equal to 100% , plus any accrued and unpaid interest, and plus a “make-whole” premium. On or after April 4, 2022, the Company may redeem all or a part of the Senior Notes at the redemption prices (expressed as percentages of principal amount) set forth below plus accrued and unpaid interest: Year Percentage On or after April 4, 2022, but before April 4, 2023 103.6 % On or after April 4, 2023, but before April 4, 2024 101.8 % On or after April 4, 2024 and thereafter 100.0 % We may also redeem the Senior Notes in whole, but not in part, at any time if changes in tax laws impose certain withholding taxes on amounts payable on the Senior Notes at a price equal to the principal amount of the Senior Notes plus accrued interest and additional amounts, if any, as may be necessary so that the net amount received by each holder after any withholding or deduction on payments of the Senior Notes will not be less than the amount such holder would have received if such taxes had not been withheld or deducted. Upon the occurrence of a change of control triggering event as defined under the Senior Notes indenture, the Company will be required to make an offer to repurchase the Senior Notes at a repurchase price equal to 101% of the principal amount, plus accrued and unpaid interest to, but excluding, the date of repurchase. If we sell assets, under certain circumstances outlined in the Senior Notes indenture, we will be required to use the net proceeds to make an offer to purchase the Senior Notes at an offer price in cash in an amount equal to 100% of the principal amount of the Senior Notes, plus accrued and unpaid interest to, but excluding, the repurchase date. The Senior Notes indenture restricts our ability and the ability of our restricted subsidiaries to, among other things: incur or guarantee additional indebtedness, create liens, pay dividends or make distributions in respect of capital stock, purchase or redeem capital stock, make investments or certain other restricted payments, sell assets, enter into agreements that restrict the ability of our subsidiaries to make dividends or other payments to us, enter into transactions with affiliates, or effect certain consolidations, mergers or amalgamations. These covenants are subject to a number of important qualifications and exceptions. Certain of these covenants will be terminated if the Senior Notes are assigned an investment grade rating by both Standard & Poor’s Rating Services and Fitch Ratings Inc. and no default or event of default has occurred and is continuing. At September 30, 2019 , the estimated repayments of debt during the five fiscal year periods and thereafter are as follows: Payments Due by Year Total 2019(2) 2020 2021 2022 2023 Thereafter (In thousands) Principal debt repayments(1) $ 2,150,000 $ — $ — $ 274,800 $ 284,200 $ 271,600 $ 1,319,400 __________________________________ (1) Includes the scheduled principal maturities for the $650.0 million aggregate principal amount of Senior Notes issued in April 2019, and borrowings under the Facility. The scheduled maturities of debt related to the Facility are based on, as of September 30, 2019 , our level of borrowings and our estimated future available borrowing base commitment levels in future periods. Any increases or decreases in the level of borrowings or increases or decreases in the available borrowing base would impact the scheduled maturities of debt during the next five years and thereafter. (2) Represents payments for the period October 1, 2019 through December 31, 2019 . Interest and other financing costs, net Interest and other financing costs, net incurred during the periods is comprised of the following: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (In thousands) Interest expense $ 34,944 $ 27,317 $ 111,566 $ 77,121 Amortization—deferred financing costs 2,285 2,346 6,974 7,069 Loss on extinguishment of debt — 268 24,794 4,324 Capitalized interest (7,077 ) (7,097 ) (21,330 ) (21,209 ) Deferred interest 290 (194 ) 1,559 (1,284 ) Interest income (972 ) (788 ) (2,215 ) (2,579 ) Other, net 1,251 1,697 4,217 4,671 Interest and other financing costs, net $ 30,721 $ 23,549 $ 125,565 $ 68,113

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments We use financial derivative contracts to manage exposures to commodity price and interest rate fluctuations. We do not hold or issue derivative financial instruments for trading purposes. We manage market and counterparty credit risk in accordance with our policies and guidelines. In accordance with these policies and guidelines, our management determines the appropriate timing and extent of derivative transactions. We have included an estimate of non-performance risk in the fair value measurement of our derivative contracts as required by ASC 820 — Fair Value Measurements and Disclosures. Oil Derivative Contracts The following table sets forth the volumes in barrels underlying the Company’s outstanding oil derivative contracts and the weighted average prices per Bbl for those contracts as of September 30, 2019 . Volumes and weighted average prices are net of any offsetting derivative contracts entered into. Weighted Average Price per Bbl Net Deferred Premium Term Type of Contract Index MBbl Payable/(Receivable) Swap Sold Put Floor Ceiling 2019: Oct — Dec Three-way collars Dated Brent 2,628 $ 1.17 $ — $ 43.81 $ 53.33 $ 73.57 Oct — Dec Sold calls(1) Dated Brent 230 — — — — 80.00 Oct — Dec Swaps NYMEX WTI 265 — 51.61 — — — Oct — Dec Collars Argus LLS 250 — — — 60.00 88.75 2020: Jan — Dec Three-way collars Dated Brent 6,000 $ 0.45 $ — $ 45.00 $ 57.50 $ 80.18 Jan — Dec Swaps with sold puts Dated Brent 2,000 — 60.53 48.75 — — Jan — Dec Put spread Dated Brent 2,000 2.59 — 50.00 60.00 — Jan — Dec Sold calls(1)(2) Dated Brent 8,000 1.17 — — — 85.00 2021: Jan — Dec Sold calls(1) Dated Brent 1,000 $ — $ — $ — $ — $ 75.00 __________________________________ (1) Represents call option contracts sold to counterparties to enhance other derivative positions. (2) Deferred premium payable to be paid October 1, 2019 — December 31, 2019. In October 2019, we entered into put option contracts for 2.0 MMBbls from January 2020 through December 2020 with a floor price of $57.50 per barrel and a sold put price of $50.00 per barrel. In addition, we sold 3.0 MMBbl of calls from January 2021 through December 2021 with an average strike price of $71.67 per barrel. The contracts are indexed to Dated Brent prices. The following tables disclose the Company’s derivative instruments as of September 30, 2019 and December 31, 2018 , and gain/(loss) from derivatives during the three and nine months ended September 30, 2019 and 2018 , respectively: Estimated Fair Value Asset (Liability) Type of Contract Balance Sheet Location September 30, December 31, (In thousands) Derivatives not designated as hedging instruments: Derivative assets: Commodity(1) Derivatives assets—current $ 22,067 $ 38,785 Commodity(2) Derivatives assets—long-term 10,535 14,312 Derivative liabilities: Commodity(3) Derivatives liabilities—current (8,461 ) (12,172 ) Commodity(4) Derivatives liabilities—long-term (2,699 ) (10,181 ) Total derivatives not designated as hedging instruments $ 21,442 $ 30,744 __________________________________ (1) Includes zero and $0.4 million as of September 30, 2019 and December 31, 2018 , respectively which represents our provisional oil sales contract. Also, includes net deferred premiums payable of $4.1 million and $1.6 million related to commodity derivative contracts as of September 30, 2019 and December 31, 2018 , respectively. (2) Includes net deferred premiums payable of $2.6 million and $1.3 million related to commodity derivative contracts as of September 30, 2019 and December 31, 2018 , respectively. (3) Includes net deferred premiums payable of $6.5 million and $18.0 million related to commodity derivative contracts as of September 30, 2019 and December 31, 2018 , respectively. (4) Includes net deferred premiums payable of zero and $0.5 million related to commodity derivative contracts as of September 30, 2019 and December 31, 2018 , respectively. Amount of Gain/(Loss) Amount of Gain/(Loss) Three Months Ended Nine Months Ended September 30, September 30, Type of Contract Location of Gain/(Loss) 2019 2018 2019 2018 (In thousands) Derivatives not designated as hedging instruments: Commodity(1) Oil and gas revenue $ 4,667 $ 3,075 $ 1,881 $ 3,584 Commodity Derivatives, net 27,016 (57,357 ) (35,884 ) (236,107 ) Interest rate Interest expense — 15 — 466 Total derivatives not designated as hedging instruments $ 31,683 $ (54,267 ) $ (34,003 ) $ (232,057 ) __________________________________ (1) Amounts represent the change in fair value of our provisional oil sales contracts. Offsetting of Derivative Assets and Derivative Liabilities Our derivative instruments which are subject to master netting arrangements with our counterparties only have the right of offset when there is an event of default. As of September 30, 2019 and December 31, 2018 , there was not an event of default and, therefore, the associated gross asset or gross liability amounts related to these arrangements are presented on the consolidated balance sheets.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements In accordance with ASC Topic 820 — Fair Value Measurements and Disclosures, fair value measurements are based upon inputs that market participants use in pricing an asset or liability, which are classified into two categories: observable inputs and unobservable inputs. Observable inputs represent market data obtained from independent sources, whereas unobservable inputs reflect a company’s own market assumptions, which are used if observable inputs are not reasonably available without undue cost and effort. We prioritize the inputs used in measuring fair value into the following fair value hierarchy: • Level 1 — quoted prices for identical assets or liabilities in active markets. • Level 2 — quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability and inputs derived principally from or corroborated by observable market data by correlation or other means. • Level 3 — unobservable inputs for the asset or liability. The fair value input hierarchy level to which an asset or liability measurement in its entirety falls is determined based on the lowest level input that is significant to the measurement in its entirety. The following tables present the Company’s assets and liabilities that are measured at fair value on a recurring basis as of September 30, 2019 and December 31, 2018 , for each fair value hierarchy level: Fair Value Measurements Using: Quoted Prices in Active Markets for Significant Other Significant Identical Assets Observable Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Total (In thousands) September 30, 2019 Assets: Commodity derivatives $ — $ 32,602 $ — $ 32,602 Liabilities: Commodity derivatives — (11,160 ) — (11,160 ) Total $ — $ 21,442 $ — $ 21,442 December 31, 2018 Assets: Commodity derivatives $ — $ 53,097 $ — $ 53,097 Liabilities: Commodity derivatives — (22,353 ) — (22,353 ) Total $ — $ 30,744 $ — $ 30,744 The book values of cash and cash equivalents and restricted cash approximate fair value based on Level 1 inputs. Joint interest billings, oil sales and other receivables, and accounts payable and accrued liabilities approximate fair value due to the short-term nature of these instruments. Our long-term receivables, after any allowances for doubtful accounts, and other long-term assets approximate fair value. The estimates of fair value of these items are based on Level 2 inputs. Commodity Derivatives Our commodity derivatives represent crude oil collars, put options, call options and swaps for notional barrels of oil at fixed Dated Brent, NYMEX WTI or Argus LLS oil prices. The values attributable to our oil derivatives are based on (i) the contracted notional volumes, (ii) independent active futures price quotes for the respective index, (iii) a credit-adjusted yield curve applicable to each counterparty by reference to the credit default swap (“CDS”) market and (iv) an independently sourced estimate of volatility for respective index. The volatility estimate was provided by certain independent brokers who are active in buying and selling oil options and was corroborated by market-quoted volatility factors. The deferred premium is included in the fair market value of the commodity derivatives. See Note 9 — Derivative Financial Instruments for additional information regarding the Company’s derivative instruments. Provisional Oil Sales The value attributable to provisional oil sales derivatives is based on (i) the sales volumes and (ii) the difference in the independent active futures price quotes for the respective index over the term of the pricing period designated in the sales contract and the spot price on the lifting date. Debt The following table presents the carrying values and fair values at September 30, 2019 and December 31, 2018 : September 30, 2019 December 31, 2018 Carrying Value Fair Value Carrying Value Fair Value (In thousands) Senior Notes $ 642,318 $ 670,514 $ — $ — Senior Secured Notes — — 511,873 525,026 Corporate Revolver — — 325,000 325,000 Facility 1,500,000 1,500,000 1,325,000 1,325,000 Total $ 2,142,318 $ 2,170,514 $ 2,161,873 $ 2,175,026 The carrying value of our Senior Notes and Senior Secured Notes represents the principal amounts outstanding less unamortized discounts. The fair value of our Senior Notes and Senior Secured Notes is based on quoted market prices, which results in a Level 1 fair value measurement. The carrying value of the Facility approximates fair value since it is subject to short-term floating interest rates that approximate the rates available to us for those periods.

Equity-based Compensation

Equity-based Compensation	9 Months Ended
	Sep. 30, 2019
Share-based Payment Arrangement [Abstract]
Equity-based Compensation	Equity-based Compensation Restricted Stock Units We record equity-based compensation expense equal to the fair value of share-based payments over the vesting periods of the Long Term Incentive Plan (“LTIP”) awards. We recorded compensation expense from awards granted under our LTIP of $9.5 million and $8.9 million during the three months ended September 30, 2019 and 2018 , respectively, and $27.4 million and $26.0 million during the nine months ended September 30, 2019 and 2018 , respectively. The total tax benefit for the three months ended was $3.1 million and $1.6 million , respectively, and $5.9 million and $5.0 million during the nine months ended September 30, 2019 and 2018 , respectively. Additionally, we recorded a net tax shortfall (windfall) related to equity-based compensation of nil and $0.1 million for the three months ended September 30, 2019 and 2018 , respectively, and $1.2 million and $(0.3) million during the nine months ended September 30, 2019 and 2018 , respectively. The fair value of awards vested during the three months ended September 30, 2019 and 2018 was approximately $0.7 million and $1.1 million , respectively, and $14.7 million and $83.1 million during the nine months ended September 30, 2019 and 2018 , respectively. The Company granted restricted stock units with service vesting criteria and a combination of market and service vesting criteria under the LTIP. Substantially all these grants vest over three years . Upon vesting, restricted stock units become issued and outstanding stock. The following table reflects the outstanding restricted stock units as of September 30, 2019 : Weighted- Market / Service Weighted- Service Vesting Average Vesting Average Restricted Stock Grant-Date Restricted Stock Grant-Date Units Fair Value Units Fair Value (In thousands) (In thousands) Outstanding at December 31, 2018 4,115 $ 6.42 6,716 $ 9.02 Granted(1) 3,096 4.96 3,160 6.02 Forfeited(1) (134 ) 6.11 (295 ) 9.87 Vested (1,999 ) 5.92 (1,300 ) 6.32 Outstanding at September 30, 2019 5,078 5.73 8,281 8.39 __________________________________ (1) The restricted stock units with a combination of market and service vesting criteria may vest between 0% and 200% of the originally granted units depending upon market performance conditions. Awards vesting over or under target shares of 100% results in additional shares granted or forfeited, respectively, in the period the market vesting criteria is determined. As of September 30, 2019 , total equity-based compensation to be recognized on unvested restricted stock units is $38.3 million over a weighted average period of 1.97 years . In March 2018, the board of directors approved an amendment to the LTIP to add 11.0 million shares to the plan, which was approved by our stockholders at the Annual General Meeting in June 2018. The LTIP provides for the issuance of 50.5 million shares pursuant to awards under the plan. At September 30, 2019 , the Company had approximately 9.8 million shares that remain available for issuance under the LTIP. For restricted stock units with a combination of market and service vesting criteria, the number of common shares to be issued is determined by comparing the Company’s total shareholder return with the total shareholder return of a predetermined group of peer companies over the performance period and can vest in up to 200% of the awards granted. The grant date fair value ranged from $4.83 to $12.96 per award. The Monte Carlo simulation model utilizes multiple input variables that determine the probability of satisfying the market condition stipulated in the award grant and calculates the fair value of the award. The expected volatility utilized in the model was estimated using our historical volatility and the historical volatilities of our peer companies and ranged from 44.0% to 52.0% . The risk-free interest rate was based on the U.S. treasury rate for a term commensurate with the expected life of the grant and ranged from 0.8% to 2.5% .

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We provide for income taxes based on the laws and rates in effect in the countries in which our operations are conducted. The relationship between our pre‑tax income or loss from continuing operations and our income tax expense or benefit varies from period to period as a result of various factors, which include changes in total pre‑tax income or loss, the jurisdictions in which our income (loss) is earned, and the tax laws in those jurisdictions. We evaluate our estimated annual effective income tax rate each quarter, based on current and forecasted business results and enacted tax laws, and apply this tax rate to our ordinary income or loss to calculate our estimated tax expense or benefit. The Company excludes zero tax rate and tax-exempt jurisdictions from our evaluation of the estimated annual effective income tax rate. The tax effect of discrete items are recognized in the period in which they occur at the applicable statutory tax rate. The company was not subject to taxation at the parent company level for the three and nine months ended September 30, 2018. For 2019, the income tax provision consists of United States, Ghanaian, and Equatorial Guinean income taxes, and Texas margin taxes. For 2018, results from operations in Equatorial Guinea were reported net of tax, as Gain on equity method investments, net in our consolidated statement of operations, and were not included in our 2018 income tax provision. Our operations in other foreign jurisdictions have a 0% effective tax rate because they reside in countries with a 0% statutory rate or we have incurred losses in those countries and have full valuation allowances against the corresponding net deferred tax assets. Income (loss) before income taxes is composed of the following: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (In thousands) United States $ 3,464 $ (53,136 ) $ (70,776 ) $ (49,967 ) Bermuda — (15,513 ) — (47,474 ) Foreign—other 36,071 (46,044 ) 98,170 (240,444 ) Income (loss) before income taxes $ 39,535 $ (114,693 ) $ 27,394 $ (337,885 ) For the three months ended , September 30, 2019 , and 2018 , our effective tax rate was 59% and 10% , respectively. For the nine months ended , September 30, 2019 , and 2018 , our effective tax rate was 173% and 17% , respectively. For the three and nine months ended September 30, 2019 , our overall effective tax rate was impacted by the difference in our 21% U.S. income tax reporting rate and the 35% statutory tax rates applicable to our Ghanaian and Equatorial Guinean operations, non-deductible and non-taxable items associated with our U.S., Ghanaian, and Equatorial Guinean operations, and other losses and expenses, primarily related to exploration operations in tax-exempt jurisdictions or in taxable jurisdictions where we have valuation allowances against our deferred tax assets, and therefore, we do not realize any tax benefit on such losses or expenses. For the three and nine months ended September 30, 2018, our overall effective tax rate was impacted by non-deductible and non-taxable items associated with our U.S. and Ghanaian operations and other losses and expenses, primarily related to exploration operations in tax-exempt jurisdictions or in taxable jurisdictions where we have valuation allowances against our deferred tax assets, and therefore, we do not realize any tax benefit on such losses or expenses. The Company files income tax returns in all jurisdictions where such requirements exist, however, our primary tax jurisdictions are the United States, Ghana and Equatorial Guinea. The Company is open to tax examinations in the United States, for federal income tax return years 2016 through 2018, in Ghana to federal income tax return years 2014 through 2018, and in Equatorial Guinea to federal income tax return year2018. As of September 30, 2019 , the Company had no material uncertain tax positions. The Company’s policy is to recognize potential interest and penalties related to income tax matters in income tax expense.

Net Income (Loss) Per Share

Net Income (Loss) Per Share	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Net Income (Loss) Per Share	Net Income (Loss) Per Share The following table is a reconciliation between net income (loss) and the amounts used to compute basic and diluted net income (loss) per share and the weighted average shares outstanding used to compute basic and diluted net income (loss) per share: Three Months Ended Nine Months Ended September 30, September 30, 2019 2018 2019 2018 (In thousands, except per share data) Numerator: Net income (loss) allocable to common stockholders $ 16,065 $ (126,057 ) $ (20,004 ) $ (279,556 ) Denominator: Weighted average number of shares outstanding: Basic 401,466 404,536 401,319 399,026 Restricted stock units(1) 9,526 — — — Diluted 410,992 404,536 401,319 399,026 Net income (loss) per share: Basic $ 0.04 $ (0.31 ) $ (0.05 ) $ (0.70 ) Diluted $ 0.04 $ (0.31 ) $ (0.05 ) $ (0.70 ) __________________________________ (1) We excluded outstanding restricted stock awards and units of 0.7 million and 13.1 million for the three months ended September 30, 2019 and 2018, respectively, and 15.4 million and 14.5 million for the nine months ended September 30, 2019 and 2018 , respectively, from the computations of diluted net income (loss) per share because the effect would have been anti-dilutive

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies From time to time, we are involved in litigation, regulatory examinations and administrative proceedings primarily arising in the ordinary course of our business in jurisdictions in which we do business. Although the outcome of these matters cannot be predicted with certainty, management believes none of these matters, either individually or in the aggregate, would have a material effect upon the Company’s financial position; however, an unfavorable outcome could have a material adverse effect on our results from operations for a specific interim period or year. We currently have a commitment to drill one exploration well in each of Sao Tome and Principe and Namibia and two exploration wells in Mauritania. In Sao Tome and Principe, we also have 3D seismic acquisition requirements of approximately 13,500 square kilometers. In South Africa we have 2D seismic acquisition requirements of approximately 500 line kilometers. Leases We have commitments under operating leases primarily related to office leases. Our leases have initial lease terms ranging from one year to ten years . Certain lease agreements contain provisions for future rent increases. The components of lease cost for the three months and nine months ended September 30, 2019 are as follows: Three months ended September 30, 2019 Nine Months Ended (In thousands) Operating lease cost $ 1,279 $ 4,288 Short-term lease cost 960 1,547 Total lease cost $ 2,239 $ 5,835 Other information related to operating leases at September 30, 2019 , is as follows: September 30, 2019 (In thousands, except lease term and discount rate) Balance sheet classifications Other assets (right-of-use assets) $ 20,436 Accrued liabilities (current maturities of leases) 1,294 Other long-term liabilities (non-current maturities of leases) 22,480 Weighted average remaining lease term 9.1 years Weighted average discount rate 9.8 % The table below presents supplemental cash flow information related to leases during the nine months ended September 30, 2019 : Nine Months Ended (In thousands) Operating cash flows for operating leases $ 3,077 Future minimum rental commitments under our leases at September 30, 2019 , are as follows: Operating Leases(1) (In thousands) 2019(2) $ 483 2020 4,098 2021 4,148 2022 4,199 2023 4,249 Thereafter 19,480 Total undiscounted lease payments $ 36,657 Less: Imputed interest (12,883 ) Total lease liabilities $ 23,774 __________________________________ (1) Does not include purchase commitments for jointly owned fields and facilities where we are not the operator and excludes commitments for exploration activities, including well commitments, in our petroleum contracts. (2) Represents payments for the period from October 1, 2019 through December 31, 2019 . Performance Obligations As of September 30, 2019 and December 31, 2018 , the Company had performance bonds totaling $208.7 million and $200.9 million , respectively, for our supplemental bonding requirements stipulated by the BOEM and $3.7 million and $3.7 million , respectively, to another operator related to costs anticipated for the plugging and abandonment of certain wells and the removal of certain facilities in our U.S. Gulf of Mexico fields. As of September 30, 2019 and December 31, 2018 , we had zero and $0.6 million , respectively, of cash collateral against these secured performance bonds which is classified as Other long term assets in our consolidated balance sheets. Dividends On November 1, 2019, we declared our quarterly cash dividend of $0.0452

Additional Financial Informatio

Additional Financial Information	9 Months Ended
	Sep. 30, 2019
Additional Financial Information
Additional Financial Information	Additional Financial Information Accrued Liabilities Accrued liabilities consisted of the following: September 30, December 31, (In thousands) Accrued liabilities: Exploration, development and production $ 114,833 $ 92,613 Revenue payable 33,721 24,379 Current asset retirement obligations 5,844 6,617 Operating leases 1,294 — General and administrative expenses 31,913 39,373 Interest 27,913 18,152 Income taxes 69,938 8,958 Taxes other than income 2,060 4,613 Derivatives 2,975 441 Other 1,928 450 $ 292,419 $ 195,596 Asset Retirement Obligations The following table summarizes the changes in the Company's asset retirement obligations: September 30, (In thousands) Asset retirement obligations: Beginning asset retirement obligations $ 151,953 Additions associated with Equatorial Guinea - Ceiba Field and Okume Complex 114,395 Liabilities incurred during period 9,706 Liabilities settled during period (4,384 ) Revisions in estimated retirement obligations 905 Accretion expense 17,795 Ending asset retirement obligations $ 290,370 With an effective date of January 1, 2019, our outstanding shares in KTIPI were transferred to Trident in exchange for a 40.375% undivided interest in the Ceiba Field and Okume Complex. As a result, our interest in the Ceiba Field and Okume Complex going forward is accounted for under the proportionate consolidation method of accounting, which includes additions to our asset retirement obligations. Facilities Insurance Modifications, Net Facilities insurance modifications, net consists of costs associated with the long-term solution to convert the Jubilee FPSO to a permanently spread moored facility, net of related insurance reimbursements. During the three months ended September 30, 2019 and 2018 , we incurred approximately $12.6 million and $12.3 million , respectively in expenditures with no offsetting insurance recoveries. During the nine months ended September 30, 2019 and 2018 , we incurred approximately $34.8 million and $31.5 million , respectively in expenditures offset by approximately $40.0 million and $9.7 million , respectively in insurance recoveries. Other Expenses, Net Other expenses, net incurred during the period is comprised of the following: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (In thousands) (Gain) loss on disposal of inventory $ 1,232 $ (2 ) $ 1,419 $ (26 ) (Gain) loss on ARO liability settlements (746 ) — 1,167 — Disputed charges and related costs, net of recoveries 1,677 (12,682 ) 1,663 (9,721 ) Other, net 9,309 (123 ) 7,549 1,583 Other expenses, net $ 11,472 $ (12,807 ) $ 11,798 $ (8,164 ) The disputed charges and related costs, net of recoveries arise from the final award issued by the International Chamber of Commerce ("ICC") in favor of Kosmos in its arbitration against Tullow Ghana Limited, related to expenditures arising from Tullow's contract with Seadrill for use of the West Leo drilling rig. Other, net is primarily related to an $8.7 million indirect tax settlement with tax authorities in Senegal.

Business Segment Information

Business Segment Information	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Business Segment Information	Business Segment Information Kosmos is engaged in a single line of business, which is the exploration, development and production of oil and gas. At September 30, 2019 , substantially all of our long-lived assets and all of our product sales are related to operations in four geographic reporting segments: Ghana, Equatorial Guinea, Mauritania/Senegal and the U.S. Gulf of Mexico. In addition, we have exploration activities in other countries in the Atlantic Margins. To assess performance of the reporting segments, the Chief Operating Decision Maker ("CODM") reviews capital expenditures. Capital expenditures, as defined by the Company, may not be comparable to similarly titled measures used by other companies and should be considered in conjunction with our consolidated financial statements and notes thereto. Financial information for each area is presented below: Ghana Equatorial Guinea Mauritania/Senegal U.S. Gulf of Mexico Corporate & Other Eliminations Total (In thousands) Three months ended September 30, 2019 Revenues and other income: Oil and gas revenue $ 177,797 $ 55,378 $ — $ 123,861 $ — $ — $ 357,036 Other income, net 1 — — 200 5,706 (5,973 ) (66 ) Total revenues and other income 177,798 55,378 — 124,061 5,706 (5,973 ) 356,970 Costs and expenses: Oil and gas production 42,017 21,369 — 32,154 — — 95,540 Facilities insurance modifications, net 12,569 — — — — — 12,569 Exploration expenses 82 2,437 1,260 10,625 8,369 — 22,773 General and administrative 3,886 1,719 2,678 7,002 38,897 (29,459 ) 24,723 Depletion, depreciation and amortization 73,347 16,019 15 56,359 913 — 146,653 Interest and other financing costs, net(1) 16,821 — (6,703 ) 5,083 17,304 (1,784 ) 30,721 Derivatives, net — — — (1,745 ) (25,271 ) — (27,016 ) Other expenses, net (25,357 ) 615 9,141 550 1,253 25,270 11,472 Total costs and expenses 123,365 42,159 6,391 110,028 41,465 (5,973 ) 317,435 Income (loss) before income taxes 54,433 13,219 (6,391 ) 14,033 (35,759 ) — 39,535 Income tax expense (benefit) 10,585 6,110 — 2,942 3,833 — 23,470 Net income (loss) $ 43,848 $ 7,109 $ (6,391 ) $ 11,091 $ (39,592 ) $ — $ 16,065 Consolidated capital expenditures $ 28,398 $ 15,397 $ 842 $ 49,629 $ 13,127 $ — $ 107,393 Ghana Equatorial Guinea Mauritania/Senegal U.S. Gulf of Mexico Corporate & Other Eliminations Total (In thousands) Nine months ended September 30, 2019 Revenues and other income: Oil and gas revenue $ 502,800 $ 208,667 $ — $ 338,292 $ — $ — $ 1,049,759 Other income, net 2 — — 459 97,594 (98,120 ) (65 ) Total revenues and other income 502,802 208,667 — 338,751 97,594 (98,120 ) 1,049,694 Costs and expenses: — Oil and gas production 117,027 60,645 — 88,644 — — 266,316 Facilities insurance modifications, net (5,174 ) — — — — — (5,174 ) Exploration expenses 189 8,080 9,745 32,834 32,174 — 83,022 General and administrative 15,844 5,303 6,505 19,288 127,416 (85,653 ) 88,703 Depletion, depreciation and amortization 204,108 55,323 46 153,768 2,941 — 416,186 Interest and other financing costs, net(1) 56,500 — (20,020 ) 16,654 77,782 (5,351 ) 125,565 Derivatives, net — — — 28,768 7,116 — 35,884 Other expenses, net 6,761 (1,629 ) 9,783 2,695 1,304 (7,116 ) 11,798 Total costs and expenses 395,255 127,722 6,059 342,651 248,733 (98,120 ) 1,022,300 Income (loss) before income taxes 107,547 80,945 (6,059 ) (3,900 ) (151,139 ) — 27,394 Income tax expense (benefit) 30,285 33,403 — (824 ) (15,466 ) — 47,398 Net income (loss) $ 77,262 $ 47,542 $ (6,059 ) $ (3,076 ) $ (135,673 ) $ — $ (20,004 ) Consolidated capital expenditures $ 96,861 $ 36,448 $ 7,132 $ 136,688 $ 41,177 $ — $ 318,306 As of September 30, 2019 Property and equipment, net $ 1,603,170 $ 460,044 $ 428,596 $ 1,263,945 $ 43,281 $ — $ 3,799,036 Total assets $ 1,844,328 $ 489,564 $ 568,743 $ 3,309,044 $ 12,078,321 $ (13,821,741 ) $ 4,468,259 ______________________________________ (1) Interest expense is recorded based on actual third-party and intercompany debt agreements. Capitalized interest is recorded on the business unit where the assets reside. Ghana Equatorial Guinea(1) Mauritania/Senegal U.S. Gulf of Mexico(2) Corporate & Other Eliminations(3) Total (In thousands) Three months ended September 30, 2018 Revenues and other income: Oil and gas revenue $ 218,656 $ 107,704 $ — $ 24,177 $ — $ (107,704 ) $ 242,833 Gain on sale of assets — 7,666 — — — — 7,666 Other income, net — (317 ) — — 78,166 (78,129 ) (280 ) Total revenues and other income 218,656 115,053 — 24,177 78,166 (185,833 ) 250,219 Costs and expenses: Oil and gas production 49,280 20,167 — 4,467 1,331 (20,167 ) 55,078 Facilities insurance modifications, net 12,334 — — — — — 12,334 Exploration expenses 57,818 16,584 1,203 50,176 22,457 — 148,238 General and administrative 5,786 1,761 1,396 4,026 42,072 (29,078 ) 25,963 Depletion, depreciation and amortization 70,799 37,291 15 8,190 1,037 (37,291 ) 80,041 Interest and other financing costs, net(4) 21,989 (4 ) (6,441 ) 2,085 7,704 (1,784 ) 23,549 Derivatives, net — — — 10,082 47,275 — 57,357 (Gain) loss on equity method investments, net — — — — — (24,841 ) (24,841 ) Other expenses, net 34,610 (976 ) (13 ) — 846 (47,274 ) (12,807 ) Total costs and expenses 252,616 74,823 (3,840 ) 79,026 122,722 (160,435 ) 364,912 Income (loss) before income taxes (33,960 ) 40,230 3,840 (54,849 ) (44,556 ) (25,398 ) (114,693 ) Income tax expense (benefit) 21,862 25,398 — (12,324 ) 1,826 (25,398 ) 11,364 Net income (loss) $ (55,822 ) $ 14,832 $ 3,840 $ (42,525 ) $ (46,382 ) $ — $ (126,057 ) Consolidated capital expenditures $ 32,501 $ 2,913 $ 3,319 $ 52,488 $ 17,970 $ — $ 109,191 Ghana Equatorial Guinea(1) Mauritania/Senegal U.S. Gulf of Mexico(2) Corporate & Other Eliminations(3) Total (In thousands) Nine months ended September 30, 2018 Revenues and other income: Oil and gas revenue $ 561,043 $ 300,079 $ — $ 24,177 $ — $ (300,079 ) $ 585,220 Gain on sale of assets — 7,666 — — — — 7,666 Other income, net (17 ) 22 — — 315,771 (315,793 ) (17 ) Total revenues and other income 561,026 307,767 — 24,177 315,771 (615,872 ) 592,869 Costs and expenses: Oil and gas production 143,860 57,683 — 4,467 3,334 (57,683 ) 151,661 Facilities insurance modifications, net 21,812 — — — — — 21,812 Exploration expenses 58,076 33,665 6,603 50,176 98,392 — 246,912 General and administrative 15,651 3,768 3,628 4,026 122,558 (84,288 ) 65,343 Depletion, depreciation and amortization 197,260 115,862 46 8,190 3,111 (115,862 ) 208,607 Interest and other financing costs, net(4) 65,357 (9 ) (18,704 ) 2,085 24,735 (5,351 ) 68,113 Derivatives, net — — — 10,082 226,025 — 236,107 (Gain) loss on equity method investments, net — — — — — (59,637 ) (59,637 ) Other expenses, net 216,319 (1,138 ) (13 ) — 2,695 (226,027 ) (8,164 ) Total costs and expenses 718,335 209,831 (8,440 ) 79,026 480,850 (548,848 ) 930,754 Income (loss) before income taxes (157,309 ) 97,936 8,440 (54,849 ) (165,079 ) (67,024 ) (337,885 ) Income tax expense (benefit) (49,148 ) 67,024 — (12,324 ) 3,143 (67,024 ) (58,329 ) Net income (loss) $ (108,161 ) $ 30,912 $ 8,440 $ (42,525 ) $ (168,222 ) $ — $ (279,556 ) Consolidated capital expenditures $ 71,330 $ 27,891 $ 9,633 $ 52,488 $ 102,651 $ — $ 263,993 As of September 30, 2018 Property and equipment, net $ 1,727,595 $ 3,801 $ 403,111 $ 1,340,479 $ 34,551 $ — $ 3,509,537 Total assets $ 2,073,825 $ 145,823 $ 465,352 $ 3,473,501 $ 10,660,832 $ (12,489,869 ) $ 4,329,464 ______________________________________ (1) Includes our proportionate share of our equity method investment in KTIPI, including our basis difference which is reflected in depletion, depreciation and amortization for the three and nine months ended September 30, 2018 , except for capital expenditures. See Note 7 - Equity Method Investments for additional information regarding our equity method investments. (2) No activity prior to September 14, 2018, the DGE acquisition date. (3) Includes elimination of proportionate consolidation amounts recorded for KTIPI to reconcile to (Gain) loss on equity method investments, net as reported in the consolidated statements of operations. (4) Interest expense is recorded based on actual third-party and intercompany debt agreements. Capitalized interest is recorded on the business unit where the assets reside. Nine Months Ended September 30, 2019 2018 (In thousands) Consolidated capital expenditures: Consolidated Statements of Cash Flows - Investing activities: Oil and gas assets $ 240,642 $ 149,305 Other property 8,291 3,560 Adjustments: Changes in capital accruals 11,083 13,965 Exploration expense, excluding unsuccessful well costs(1) 75,661 131,964 Capitalized interest (21,330 ) (21,209 ) Proceeds on sale of assets — (13,703 ) Other 3,959 111 Total consolidated capital expenditures $ 318,306 $ 263,993 ______________________________________ (1) Unsuccessful well costs are included in oil and gas assets when incurred.

Accounting Policies (Policies)

Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
General	General The interim consolidated financial statements included in this report are unaudited and, in the opinion of management, include all adjustments of a normal recurring nature necessary for a fair presentation of the results for the interim periods. The results of the interim periods shown in this report are not necessarily indicative of the final results to be expected for the full year. The consolidated financial statements were prepared in accordance with the requirements of the Securities and Exchange Commission (“SEC”) for interim reporting. As permitted under those rules, certain notes or other financial information that are normally required by Generally Accepted Accounting Principles in the United States of America (“GAAP”) have been condensed or omitted from these interim consolidated financial statements. These consolidated financial statements and the accompanying notes should be read in conjunction with our audited consolidated financial statements for the year ended December 31, 2018 , included in our annual report on Form 10-K.
Reclassifications	Reclassifications Certain prior period amounts have been reclassified to conform with the current presentation. Such reclassifications had no significant impact on our reported net income (loss) , current assets, total assets, current liabilities, total liabilities, stockholders’ equity or cash flows. Additionally, as a result of our outstanding shares in KTIPI being transferred for an undivided interest in the Ceiba Field and Okume Complex (effective January 1, 2019), our previously reported equity method investment in KTIPI has been allocated to the respective assets and liabilities on a relative fair value basis. See Note 7 — Equity Method Investments for additional information.
Cash, Cash Equivalents and Restricted Cash	Cash and cash equivalents include demand deposits and funds invested in highly liquid instruments with original maturities of three months or less at the date of purchase. In accordance with certain of our petroleum contracts, we have posted letters of credit related to performance guarantees for our minimum work obligations. Certain of these letters of credit are cash collateralized in accounts held by us and as such are classified as restricted cash. Upon completion of the minimum work obligations and/or entering into the next phase of the respective petroleum contract, the requirement to post the existing letters of credit will be satisfied and the cash collateral will be released. However, additional letters of credit may be required should we choose to move into the next phase of certain of our petroleum contracts. Cash, Cash Equivalents and Restricted Cash
Inventories	Inventories Hydrocarbon inventory is carried at the lower of cost, using the weighted average cost method, or net realizable value. Hydrocarbon inventory costs include expenditures and other charges incurred in bringing the inventory to its existing condition. Selling expenses and general and administrative expenses are reported as period costs and excluded from inventory costs.
Leases (Policy applicable beginning January 1, 2019)	Leases (Policy applicable beginning January 1, 2019) In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842).” ASU 2016-02 was issued to increase transparency and comparability across organizations by recognizing substantially all leases on the balance sheet through the concept of right-of-use lease assets and liabilities. Under prior accounting guidance, lessees did not recognize lease assets or liabilities for leases classified as operating leases. The ASU was effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years with early adoption permitted. In July 2018, the FASB issued ASU 2018-11, which added a transition option permitting entities to apply the provisions of the new standard at its adoption date instead of the earliest comparative period presented in the consolidated financial statements. Under this transition option, comparative reporting would not be required, and the provisions of the standard would be applied prospectively to leases in effect at the date of adoption. The Company adopted the guidance prospectively during the first quarter of 2019. As part of our adoption, we elected not to reassess historical lease classification, recognize short-term leases on our balance sheet, nor separate lease and non-lease components for our real estate leases. The adoption and implementation of this ASU resulted in a $21.7 million increase in assets and liabilities related to our leasing activities, which primarily consists of office leases. Our adoption of ASU 2016-02 did not impact retained earnings or other components of equity as of December 31, 2018. We account for leases in accordance with ASC Topic 842, Leases, (“ASC 842”). We determine if an arrangement is a lease at contract inception. A lease exists when a contract conveys to the customer the right to control the use of identified property, plant, or equipment for a period of time in exchange for consideration. The definition of a lease embodies two conditions: (1) there is an identified asset in the contract that is land or a depreciable asset (i.e., property, plant, and equipment), and (2) the customer has the right to control the use of the identified asset. In the normal course of business, the Company enters into various lease agreements for real estate and equipment related to its exploration, development and production activities that are currently accounted for as operating leases. Operating leases are included in Other assets, Accrued liabilities, and Other long-term liabilities on our consolidated balance sheets. The lease liabilities are initially and subsequently measured at the present value of the unpaid lease payments at the lease commencement date. Key estimates and judgments include how we determined: (1) the discount rate we use to discount the unpaid lease payments to present value; (2) lease term; and (3) lease payments. 1. ASC 842 requires a lessee to discount its unpaid lease payments using the interest rate implicit in the lease or, if that rate cannot be readily determined, its incremental borrowing rate. As most of our leases where we are the lessee do not provide an implicit rate, we use our incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. Our incremental borrowing rate for a lease is the rate of interest we would have to pay on a collateralized basis to borrow an amount equal to the lease payments under similar terms. 2. The lease term for all of our leases includes the non-cancellable period of the lease plus any additional periods covered by either an option to extend (or not to terminate) the lease that we are reasonably certain to exercise, or an option to extend (or not to terminate) the lease controlled by the lessor. 3. Lease payments included in the measurement of the lease asset or liability comprise the following: fixed payments (including in-substance fixed payments), variable payments that depend on index or rate, and the exercise price of a lessee option to purchase the underlying asset if we are reasonably certain to exercise. Amounts expected to be payable under residual value guarantee are also lease payments included in the measurement of the lease liability. The Right-of-use ("ROU") asset is initially measured at cost, which comprises the initial amount of the lease liability adjusted for lease payments made at or before the lease commencement date, plus any initial direct costs incurred less any lease incentives received. For operating leases, the ROU asset is subsequently measured throughout the lease term at the carrying amount of the lease liability, plus initial direct costs, plus (minus) any prepaid (accrued) lease payments, less the unamortized balance of lease incentives received. Lease expense for lease payments is recognized on a straight-line basis over the lease term. We monitor for events or changes in circumstances that require a reassessment of a lease. When a reassessment results in the re-measurement of a lease liability, a corresponding adjustment is made to the carrying amount of the corresponding ROU asset unless doing so would reduce the carrying amount of the ROU asset to an amount less than zero. In that case, the amount of the adjustment that would result in a negative ROU asset balance is recorded in profit or loss. We have lease agreements which include lease and non-lease components. We have elected to combine lease and non-lease components for all lease contracts. We have elected not to recognize ROU assets and lease liabilities for all short-term leases that have a lease term of 12 months or less. We recognize the lease payments associated with our short-term leases as an expense on a straight-line basis over the lease term. We adopted ASU 2016-02 using a modified retrospective transition approach as of the effective date as permitted by the amendments in ASU 2018-11, which provides an alternative modified retrospective transition method. As a result, we were not required to adjust our comparative period financial information for effects of the standard or make the new required lease disclosures for periods before the date of adoption (i.e. January 1, 2019). We have elected to adopt the package of transition practical expedients and, therefore, have not reassessed (1) whether existing or expired contracts contain a lease, (2) lease classification for existing or expired leases or (3) the accounting for initial direct costs that were previously capitalized. We did not elect the practical expedient to use hindsight for leases existing at the adoption date.
Revenue Recognition	Revenue Recognition Our oil and gas revenues are recognized when hydrocarbons have been sold to a purchaser at a fixed or determinable price, title has transferred and collection is probable. Certain revenues are based on provisional price contracts which contain an embedded derivative that is required to be separated from the host contract for accounting purposes. The host contract is the receivable from oil sales at the spot price on the date of sale. The embedded derivative, which is not designated as a hedge, is marked to market through oil and gas revenue each period until the final settlement occurs, which generally is limited to the month after the sale.
Concentration of Credit Risk	Concentration of Credit Risk
Recent Accounting Standards	Recent Accounting Standards

Accounting Policies (Tables)

Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Schedule of cash and cash equivalents	September 30, December 31, (In thousands) Cash and cash equivalents $ 203,646 $ 173,515 Restricted cash - current 7,745 4,527 Restricted cash - long-term 3,667 7,574 Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows $ 215,058 $ 185,616
Schedule of oil and gas revenue	Oil and gas revenue is composed of the following: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (In thousands) Revenues from contract with customer - Equatorial Guinea $ 54,894 $ — $ 207,173 $ — Revenues from contract with customer - Ghana 173,613 215,581 502,413 557,459 Revenues from contract with customers - U.S. Gulf of Mexico 123,861 24,177 338,292 24,177 Provisional oil sales contracts 4,668 3,075 1,881 3,584 Oil and gas revenue $ 357,036 $ 242,833 $ 1,049,759 $ 585,220

Property and Equipment (Tables)

Property and Equipment (Tables)	9 Months Ended
	Sep. 30, 2019
Property, Plant and Equipment [Abstract]
Schedule of property and equipment	Property and equipment is stated at cost and consisted of the following: September 30, December 31, (In thousands) Oil and gas properties: Proved properties $ 4,827,304 $ 4,236,489 Unproved properties 898,855 759,472 Total oil and gas properties 5,726,159 4,995,961 Accumulated depletion (1,945,170 ) (1,551,097 ) Oil and gas properties, net 3,780,989 3,444,864 Other property 59,515 51,987 Accumulated depreciation (41,468 ) (37,150 ) Other property, net 18,047 14,837 Property and equipment, net $ 3,799,036 $ 3,459,701

Suspended Well Costs (Tables)

Suspended Well Costs (Tables)	9 Months Ended
	Sep. 30, 2019
Oil and Gas Exploration and Production Industries Disclosures [Abstract]
Schedule of capitalized exploratory well costs	The following table reflects the Company’s capitalized exploratory well costs on drilled wells as of and during the nine months ended September 30, 2019 . The table excludes $1.4 million in costs that were capitalized and subsequently expensed during the same period. September 30, (In thousands) Beginning balance $ 367,665 Additions to capitalized exploratory well costs pending the determination of proved reserves 55,244 Reclassification due to determination of proved reserves (10,711 ) Capitalized exploratory well costs charged to expense — Ending balance $ 412,198
Schedule of aging of capitalized exploratory well costs and number of projects for which exploratory well costs were capitalized for more than one year	The following table provides an aging of capitalized exploratory well costs based on the date drilling was completed and the number of projects for which exploratory well costs have been capitalized for more than one year since the completion of drilling: September 30, 2019 December 31, 2018 (In thousands, except well counts) Exploratory well costs capitalized for a period of one year or less $ — $ — Exploratory well costs capitalized for a period of one to two years 77,995 299,253 Exploratory well costs capitalized for a period of three years or greater 334,203 68,412 Ending balance $ 412,198 $ 367,665 Number of projects that have exploratory well costs that have been capitalized for a period greater than one year 3 3

Equity Method Investments (Tabl

Equity Method Investments (Tables)	9 Months Ended
	Sep. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Summary of financial information of KTIPI	Below is a summary of financial information for KTIPI presented on a 100% basis for 2018. The financial information for 2019 is presented as part of our consolidated financial statements based on our direct 40.375% ownership in the Ceiba Field and Okume Complex. December 31, 2018 (In thousands) Assets Total current assets $ 149,950 Property and equipment, net 271,627 Other assets 21 Total assets $ 421,598 Liabilities and stockholders' equity Total current liabilities $ 226,311 Total long-term liabilities 536,178 Shareholders' equity: Total shareholders' equity (340,891 ) Total liabilities and shareholders' equity $ 421,598 Three Months Ended Nine Months Ended (In thousands) Revenues and other income: Oil and gas revenue $ 215,408 $ 600,158 Other income (72 ) 44 Total revenues and other income 215,336 600,202 Costs and expenses: Oil and gas production 40,334 115,366 Depletion, depreciation and amortization 33,044 108,996 Other expenses, net (58 ) (211 ) Total costs and expenses 73,320 224,151 Income before income taxes 142,016 376,051 Income tax expense 50,796 134,047 Net income $ 91,220 $ 242,004 Kosmos' share of net income $ 45,610 $ 121,002 Basis difference amortization(1) 20,769 61,365 Equity in earnings - KTIPI $ 24,841 $ 59,637 ______________________________________ (1) The basis difference, which was associated with oil and gas properties and subject to amortization, has been allocated to the Ceiba Field and Okume Complex. We amortized the basis difference using the unit-of-production method.
Schedule of asset acquisition	Carrying Value Allocation (in thousands) Assets acquired: Proved oil and gas properties $ 372,144 Unproved oil and gas properties 103,909 Prepaids and other 7,273 Total assets acquired $ 483,326 Liabilities assumed: Asset retirement obligations $ 114,395 Deferred tax liabilities 247,636 Accrued liabilities and other 69,399 Total liabilities assumed $ 431,430 Carrying value: Equity method investment carrying value at December 31, 2018 $ 51,896

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Schedule of debt	September 30, December 31, (In thousands) Outstanding debt principal balances: Facility $ 1,500,000 $ 1,325,000 Corporate Revolver — 325,000 Senior Notes 650,000 — Senior Secured Notes — 525,000 Total 2,150,000 2,175,000 Unamortized deferred financing costs and discounts(1) (43,798 ) (54,453 ) Long-term debt, net $ 2,106,202 $ 2,120,547 __________________________________ (1) Includes $34.4 million and $40.5 million of unamortized deferred financing costs related to the Facility as of September 30, 2019 and December 31, 2018 , respectively; $9.4 million of unamortized deferred financing costs and discounts related to the Senior Notes as of September 30, 2019 ; and $14.0 million of unamortized deferred financing costs and discounts related to the Senior Secured Notes as of December 31, 2018 , respectively.
Schedule of redemption prices (expressed as percentages of principal amount) of all or a part of the Senior Notes	On or after April 4, 2022, the Company may redeem all or a part of the Senior Notes at the redemption prices (expressed as percentages of principal amount) set forth below plus accrued and unpaid interest: Year Percentage On or after April 4, 2022, but before April 4, 2023 103.6 % On or after April 4, 2023, but before April 4, 2024 101.8 % On or after April 4, 2024 and thereafter 100.0 %
Schedule of estimated repayments of debt	At September 30, 2019 , the estimated repayments of debt during the five fiscal year periods and thereafter are as follows: Payments Due by Year Total 2019(2) 2020 2021 2022 2023 Thereafter (In thousands) Principal debt repayments(1) $ 2,150,000 $ — $ — $ 274,800 $ 284,200 $ 271,600 $ 1,319,400 __________________________________ (1) Includes the scheduled principal maturities for the $650.0 million aggregate principal amount of Senior Notes issued in April 2019, and borrowings under the Facility. The scheduled maturities of debt related to the Facility are based on, as of September 30, 2019 , our level of borrowings and our estimated future available borrowing base commitment levels in future periods. Any increases or decreases in the level of borrowings or increases or decreases in the available borrowing base would impact the scheduled maturities of debt during the next five years and thereafter. (2) Represents payments for the period October 1, 2019 through December 31, 2019 .
Schedule of interest and other financing costs, net	Interest and other financing costs, net incurred during the periods is comprised of the following: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (In thousands) Interest expense $ 34,944 $ 27,317 $ 111,566 $ 77,121 Amortization—deferred financing costs 2,285 2,346 6,974 7,069 Loss on extinguishment of debt — 268 24,794 4,324 Capitalized interest (7,077 ) (7,097 ) (21,330 ) (21,209 ) Deferred interest 290 (194 ) 1,559 (1,284 ) Interest income (972 ) (788 ) (2,215 ) (2,579 ) Other, net 1,251 1,697 4,217 4,671 Interest and other financing costs, net $ 30,721 $ 23,549 $ 125,565 $ 68,113

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of oil derivative contracts	The following table sets forth the volumes in barrels underlying the Company’s outstanding oil derivative contracts and the weighted average prices per Bbl for those contracts as of September 30, 2019 . Volumes and weighted average prices are net of any offsetting derivative contracts entered into. Weighted Average Price per Bbl Net Deferred Premium Term Type of Contract Index MBbl Payable/(Receivable) Swap Sold Put Floor Ceiling 2019: Oct — Dec Three-way collars Dated Brent 2,628 $ 1.17 $ — $ 43.81 $ 53.33 $ 73.57 Oct — Dec Sold calls(1) Dated Brent 230 — — — — 80.00 Oct — Dec Swaps NYMEX WTI 265 — 51.61 — — — Oct — Dec Collars Argus LLS 250 — — — 60.00 88.75 2020: Jan — Dec Three-way collars Dated Brent 6,000 $ 0.45 $ — $ 45.00 $ 57.50 $ 80.18 Jan — Dec Swaps with sold puts Dated Brent 2,000 — 60.53 48.75 — — Jan — Dec Put spread Dated Brent 2,000 2.59 — 50.00 60.00 — Jan — Dec Sold calls(1)(2) Dated Brent 8,000 1.17 — — — 85.00 2021: Jan — Dec Sold calls(1) Dated Brent 1,000 $ — $ — $ — $ — $ 75.00 __________________________________ (1) Represents call option contracts sold to counterparties to enhance other derivative positions. (2) Deferred premium payable to be paid October 1, 2019 — December 31, 2019.
Schedule of derivative instruments by balance sheet location	The following tables disclose the Company’s derivative instruments as of September 30, 2019 and December 31, 2018 , and gain/(loss) from derivatives during the three and nine months ended September 30, 2019 and 2018 , respectively: Estimated Fair Value Asset (Liability) Type of Contract Balance Sheet Location September 30, December 31, (In thousands) Derivatives not designated as hedging instruments: Derivative assets: Commodity(1) Derivatives assets—current $ 22,067 $ 38,785 Commodity(2) Derivatives assets—long-term 10,535 14,312 Derivative liabilities: Commodity(3) Derivatives liabilities—current (8,461 ) (12,172 ) Commodity(4) Derivatives liabilities—long-term (2,699 ) (10,181 ) Total derivatives not designated as hedging instruments $ 21,442 $ 30,744 __________________________________ (1) Includes zero and $0.4 million as of September 30, 2019 and December 31, 2018 , respectively which represents our provisional oil sales contract. Also, includes net deferred premiums payable of $4.1 million and $1.6 million related to commodity derivative contracts as of September 30, 2019 and December 31, 2018 , respectively. (2) Includes net deferred premiums payable of $2.6 million and $1.3 million related to commodity derivative contracts as of September 30, 2019 and December 31, 2018 , respectively. (3) Includes net deferred premiums payable of $6.5 million and $18.0 million related to commodity derivative contracts as of September 30, 2019 and December 31, 2018 , respectively. (4) Includes net deferred premiums payable of zero and $0.5 million related to commodity derivative contracts as of September 30, 2019 and December 31, 2018 , respectively.
Schedule of derivative instruments by location of gain/(loss)	Amount of Gain/(Loss) Amount of Gain/(Loss) Three Months Ended Nine Months Ended September 30, September 30, Type of Contract Location of Gain/(Loss) 2019 2018 2019 2018 (In thousands) Derivatives not designated as hedging instruments: Commodity(1) Oil and gas revenue $ 4,667 $ 3,075 $ 1,881 $ 3,584 Commodity Derivatives, net 27,016 (57,357 ) (35,884 ) (236,107 ) Interest rate Interest expense — 15 — 466 Total derivatives not designated as hedging instruments $ 31,683 $ (54,267 ) $ (34,003 ) $ (232,057 ) __________________________________ (1) Amounts represent the change in fair value of our provisional oil sales contracts.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Schedule of Company's assets and liabilities that are measured at fair value on a recurring basis	The following tables present the Company’s assets and liabilities that are measured at fair value on a recurring basis as of September 30, 2019 and December 31, 2018 , for each fair value hierarchy level: Fair Value Measurements Using: Quoted Prices in Active Markets for Significant Other Significant Identical Assets Observable Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Total (In thousands) September 30, 2019 Assets: Commodity derivatives $ — $ 32,602 $ — $ 32,602 Liabilities: Commodity derivatives — (11,160 ) — (11,160 ) Total $ — $ 21,442 $ — $ 21,442 December 31, 2018 Assets: Commodity derivatives $ — $ 53,097 $ — $ 53,097 Liabilities: Commodity derivatives — (22,353 ) — (22,353 ) Total $ — $ 30,744 $ — $ 30,744
Schedule of carrying values and fair values of financial instruments that are not carried at fair value	The following table presents the carrying values and fair values at September 30, 2019 and December 31, 2018 : September 30, 2019 December 31, 2018 Carrying Value Fair Value Carrying Value Fair Value (In thousands) Senior Notes $ 642,318 $ 670,514 $ — $ — Senior Secured Notes — — 511,873 525,026 Corporate Revolver — — 325,000 325,000 Facility 1,500,000 1,500,000 1,325,000 1,325,000 Total $ 2,142,318 $ 2,170,514 $ 2,161,873 $ 2,175,026

Equity-based Compensation (Tabl

Equity-based Compensation (Tables)	9 Months Ended
	Sep. 30, 2019
Share-based Payment Arrangement [Abstract]
Schedule of plan activity	The following table reflects the outstanding restricted stock units as of September 30, 2019 : Weighted- Market / Service Weighted- Service Vesting Average Vesting Average Restricted Stock Grant-Date Restricted Stock Grant-Date Units Fair Value Units Fair Value (In thousands) (In thousands) Outstanding at December 31, 2018 4,115 $ 6.42 6,716 $ 9.02 Granted(1) 3,096 4.96 3,160 6.02 Forfeited(1) (134 ) 6.11 (295 ) 9.87 Vested (1,999 ) 5.92 (1,300 ) 6.32 Outstanding at September 30, 2019 5,078 5.73 8,281 8.39 __________________________________ (1) The restricted stock units with a combination of market and service vesting criteria may vest between 0% and 200% of the originally granted units depending upon market performance conditions. Awards vesting over or under target shares of 100% results in additional shares granted or forfeited, respectively, in the period the market vesting criteria is determined.

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Schedule of components of income (loss) before income taxes	Income (loss) before income taxes is composed of the following: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (In thousands) United States $ 3,464 $ (53,136 ) $ (70,776 ) $ (49,967 ) Bermuda — (15,513 ) — (47,474 ) Foreign—other 36,071 (46,044 ) 98,170 (240,444 ) Income (loss) before income taxes $ 39,535 $ (114,693 ) $ 27,394 $ (337,885 )

Net Income (Loss) Per Share (Ta

Net Income (Loss) Per Share (Tables)	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Schedule of reconciliation between net income (loss) and amounts used to compute basic and diluted EPS	The following table is a reconciliation between net income (loss) and the amounts used to compute basic and diluted net income (loss) per share and the weighted average shares outstanding used to compute basic and diluted net income (loss) per share: Three Months Ended Nine Months Ended September 30, September 30, 2019 2018 2019 2018 (In thousands, except per share data) Numerator: Net income (loss) allocable to common stockholders $ 16,065 $ (126,057 ) $ (20,004 ) $ (279,556 ) Denominator: Weighted average number of shares outstanding: Basic 401,466 404,536 401,319 399,026 Restricted stock units(1) 9,526 — — — Diluted 410,992 404,536 401,319 399,026 Net income (loss) per share: Basic $ 0.04 $ (0.31 ) $ (0.05 ) $ (0.70 ) Diluted $ 0.04 $ (0.31 ) $ (0.05 ) $ (0.70 ) __________________________________ (1) We excluded outstanding restricted stock awards and units of 0.7 million and 13.1 million for the three months ended September 30, 2019 and 2018, respectively, and 15.4 million and 14.5 million for the nine months ended September 30, 2019 and 2018 , respectively, from the computations of diluted net income (loss) per share because the effect would have been anti-dilutive

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Components of Lease Costs and Cash Flow Information	The table below presents supplemental cash flow information related to leases during the nine months ended September 30, 2019 : Nine Months Ended (In thousands) Operating cash flows for operating leases $ 3,077 The components of lease cost for the three months and nine months ended September 30, 2019 are as follows: Three months ended September 30, 2019 Nine Months Ended (In thousands) Operating lease cost $ 1,279 $ 4,288 Short-term lease cost 960 1,547 Total lease cost $ 2,239 $ 5,835
Schedule of Other Information on Leases	Other information related to operating leases at September 30, 2019 , is as follows: September 30, 2019 (In thousands, except lease term and discount rate) Balance sheet classifications Other assets (right-of-use assets) $ 20,436 Accrued liabilities (current maturities of leases) 1,294 Other long-term liabilities (non-current maturities of leases) 22,480 Weighted average remaining lease term 9.1 years Weighted average discount rate 9.8 %
Schedule of Future Minimum Rental Commitments	Future minimum rental commitments under our leases at September 30, 2019 , are as follows: Operating Leases(1) (In thousands) 2019(2) $ 483 2020 4,098 2021 4,148 2022 4,199 2023 4,249 Thereafter 19,480 Total undiscounted lease payments $ 36,657 Less: Imputed interest (12,883 ) Total lease liabilities $ 23,774 __________________________________ (1) Does not include purchase commitments for jointly owned fields and facilities where we are not the operator and excludes commitments for exploration activities, including well commitments, in our petroleum contracts. (2) Represents payments for the period from October 1, 2019 through December 31, 2019 .

Additional Financial Informat_2

Additional Financial Information (Tables)	9 Months Ended
	Sep. 30, 2019
Additional Financial Information
Schedule of accrued liabilities	Accrued liabilities consisted of the following: September 30, December 31, (In thousands) Accrued liabilities: Exploration, development and production $ 114,833 $ 92,613 Revenue payable 33,721 24,379 Current asset retirement obligations 5,844 6,617 Operating leases 1,294 — General and administrative expenses 31,913 39,373 Interest 27,913 18,152 Income taxes 69,938 8,958 Taxes other than income 2,060 4,613 Derivatives 2,975 441 Other 1,928 450 $ 292,419 $ 195,596
Schedule of changes in asset retirement obligations	The following table summarizes the changes in the Company's asset retirement obligations: September 30, (In thousands) Asset retirement obligations: Beginning asset retirement obligations $ 151,953 Additions associated with Equatorial Guinea - Ceiba Field and Okume Complex 114,395 Liabilities incurred during period 9,706 Liabilities settled during period (4,384 ) Revisions in estimated retirement obligations 905 Accretion expense 17,795 Ending asset retirement obligations $ 290,370
Schedule of other expenses, net incurred	Other expenses, net incurred during the period is comprised of the following: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (In thousands) (Gain) loss on disposal of inventory $ 1,232 $ (2 ) $ 1,419 $ (26 ) (Gain) loss on ARO liability settlements (746 ) — 1,167 — Disputed charges and related costs, net of recoveries 1,677 (12,682 ) 1,663 (9,721 ) Other, net 9,309 (123 ) 7,549 1,583 Other expenses, net $ 11,472 $ (12,807 ) $ 11,798 $ (8,164 )

Business Segment Information (T

Business Segment Information (Tables)	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Schedule of business segment information	Financial information for each area is presented below: Ghana Equatorial Guinea Mauritania/Senegal U.S. Gulf of Mexico Corporate & Other Eliminations Total (In thousands) Three months ended September 30, 2019 Revenues and other income: Oil and gas revenue $ 177,797 $ 55,378 $ — $ 123,861 $ — $ — $ 357,036 Other income, net 1 — — 200 5,706 (5,973 ) (66 ) Total revenues and other income 177,798 55,378 — 124,061 5,706 (5,973 ) 356,970 Costs and expenses: Oil and gas production 42,017 21,369 — 32,154 — — 95,540 Facilities insurance modifications, net 12,569 — — — — — 12,569 Exploration expenses 82 2,437 1,260 10,625 8,369 — 22,773 General and administrative 3,886 1,719 2,678 7,002 38,897 (29,459 ) 24,723 Depletion, depreciation and amortization 73,347 16,019 15 56,359 913 — 146,653 Interest and other financing costs, net(1) 16,821 — (6,703 ) 5,083 17,304 (1,784 ) 30,721 Derivatives, net — — — (1,745 ) (25,271 ) — (27,016 ) Other expenses, net (25,357 ) 615 9,141 550 1,253 25,270 11,472 Total costs and expenses 123,365 42,159 6,391 110,028 41,465 (5,973 ) 317,435 Income (loss) before income taxes 54,433 13,219 (6,391 ) 14,033 (35,759 ) — 39,535 Income tax expense (benefit) 10,585 6,110 — 2,942 3,833 — 23,470 Net income (loss) $ 43,848 $ 7,109 $ (6,391 ) $ 11,091 $ (39,592 ) $ — $ 16,065 Consolidated capital expenditures $ 28,398 $ 15,397 $ 842 $ 49,629 $ 13,127 $ — $ 107,393 Ghana Equatorial Guinea Mauritania/Senegal U.S. Gulf of Mexico Corporate & Other Eliminations Total (In thousands) Nine months ended September 30, 2019 Revenues and other income: Oil and gas revenue $ 502,800 $ 208,667 $ — $ 338,292 $ — $ — $ 1,049,759 Other income, net 2 — — 459 97,594 (98,120 ) (65 ) Total revenues and other income 502,802 208,667 — 338,751 97,594 (98,120 ) 1,049,694 Costs and expenses: — Oil and gas production 117,027 60,645 — 88,644 — — 266,316 Facilities insurance modifications, net (5,174 ) — — — — — (5,174 ) Exploration expenses 189 8,080 9,745 32,834 32,174 — 83,022 General and administrative 15,844 5,303 6,505 19,288 127,416 (85,653 ) 88,703 Depletion, depreciation and amortization 204,108 55,323 46 153,768 2,941 — 416,186 Interest and other financing costs, net(1) 56,500 — (20,020 ) 16,654 77,782 (5,351 ) 125,565 Derivatives, net — — — 28,768 7,116 — 35,884 Other expenses, net 6,761 (1,629 ) 9,783 2,695 1,304 (7,116 ) 11,798 Total costs and expenses 395,255 127,722 6,059 342,651 248,733 (98,120 ) 1,022,300 Income (loss) before income taxes 107,547 80,945 (6,059 ) (3,900 ) (151,139 ) — 27,394 Income tax expense (benefit) 30,285 33,403 — (824 ) (15,466 ) — 47,398 Net income (loss) $ 77,262 $ 47,542 $ (6,059 ) $ (3,076 ) $ (135,673 ) $ — $ (20,004 ) Consolidated capital expenditures $ 96,861 $ 36,448 $ 7,132 $ 136,688 $ 41,177 $ — $ 318,306 As of September 30, 2019 Property and equipment, net $ 1,603,170 $ 460,044 $ 428,596 $ 1,263,945 $ 43,281 $ — $ 3,799,036 Total assets $ 1,844,328 $ 489,564 $ 568,743 $ 3,309,044 $ 12,078,321 $ (13,821,741 ) $ 4,468,259 ______________________________________ (1) Interest expense is recorded based on actual third-party and intercompany debt agreements. Capitalized interest is recorded on the business unit where the assets reside. Ghana Equatorial Guinea(1) Mauritania/Senegal U.S. Gulf of Mexico(2) Corporate & Other Eliminations(3) Total (In thousands) Three months ended September 30, 2018 Revenues and other income: Oil and gas revenue $ 218,656 $ 107,704 $ — $ 24,177 $ — $ (107,704 ) $ 242,833 Gain on sale of assets — 7,666 — — — — 7,666 Other income, net — (317 ) — — 78,166 (78,129 ) (280 ) Total revenues and other income 218,656 115,053 — 24,177 78,166 (185,833 ) 250,219 Costs and expenses: Oil and gas production 49,280 20,167 — 4,467 1,331 (20,167 ) 55,078 Facilities insurance modifications, net 12,334 — — — — — 12,334 Exploration expenses 57,818 16,584 1,203 50,176 22,457 — 148,238 General and administrative 5,786 1,761 1,396 4,026 42,072 (29,078 ) 25,963 Depletion, depreciation and amortization 70,799 37,291 15 8,190 1,037 (37,291 ) 80,041 Interest and other financing costs, net(4) 21,989 (4 ) (6,441 ) 2,085 7,704 (1,784 ) 23,549 Derivatives, net — — — 10,082 47,275 — 57,357 (Gain) loss on equity method investments, net — — — — — (24,841 ) (24,841 ) Other expenses, net 34,610 (976 ) (13 ) — 846 (47,274 ) (12,807 ) Total costs and expenses 252,616 74,823 (3,840 ) 79,026 122,722 (160,435 ) 364,912 Income (loss) before income taxes (33,960 ) 40,230 3,840 (54,849 ) (44,556 ) (25,398 ) (114,693 ) Income tax expense (benefit) 21,862 25,398 — (12,324 ) 1,826 (25,398 ) 11,364 Net income (loss) $ (55,822 ) $ 14,832 $ 3,840 $ (42,525 ) $ (46,382 ) $ — $ (126,057 ) Consolidated capital expenditures $ 32,501 $ 2,913 $ 3,319 $ 52,488 $ 17,970 $ — $ 109,191 Ghana Equatorial Guinea(1) Mauritania/Senegal U.S. Gulf of Mexico(2) Corporate & Other Eliminations(3) Total (In thousands) Nine months ended September 30, 2018 Revenues and other income: Oil and gas revenue $ 561,043 $ 300,079 $ — $ 24,177 $ — $ (300,079 ) $ 585,220 Gain on sale of assets — 7,666 — — — — 7,666 Other income, net (17 ) 22 — — 315,771 (315,793 ) (17 ) Total revenues and other income 561,026 307,767 — 24,177 315,771 (615,872 ) 592,869 Costs and expenses: Oil and gas production 143,860 57,683 — 4,467 3,334 (57,683 ) 151,661 Facilities insurance modifications, net 21,812 — — — — — 21,812 Exploration expenses 58,076 33,665 6,603 50,176 98,392 — 246,912 General and administrative 15,651 3,768 3,628 4,026 122,558 (84,288 ) 65,343 Depletion, depreciation and amortization 197,260 115,862 46 8,190 3,111 (115,862 ) 208,607 Interest and other financing costs, net(4) 65,357 (9 ) (18,704 ) 2,085 24,735 (5,351 ) 68,113 Derivatives, net — — — 10,082 226,025 — 236,107 (Gain) loss on equity method investments, net — — — — — (59,637 ) (59,637 ) Other expenses, net 216,319 (1,138 ) (13 ) — 2,695 (226,027 ) (8,164 ) Total costs and expenses 718,335 209,831 (8,440 ) 79,026 480,850 (548,848 ) 930,754 Income (loss) before income taxes (157,309 ) 97,936 8,440 (54,849 ) (165,079 ) (67,024 ) (337,885 ) Income tax expense (benefit) (49,148 ) 67,024 — (12,324 ) 3,143 (67,024 ) (58,329 ) Net income (loss) $ (108,161 ) $ 30,912 $ 8,440 $ (42,525 ) $ (168,222 ) $ — $ (279,556 ) Consolidated capital expenditures $ 71,330 $ 27,891 $ 9,633 $ 52,488 $ 102,651 $ — $ 263,993 As of September 30, 2018 Property and equipment, net $ 1,727,595 $ 3,801 $ 403,111 $ 1,340,479 $ 34,551 $ — $ 3,509,537 Total assets $ 2,073,825 $ 145,823 $ 465,352 $ 3,473,501 $ 10,660,832 $ (12,489,869 ) $ 4,329,464 ______________________________________ (1) Includes our proportionate share of our equity method investment in KTIPI, including our basis difference which is reflected in depletion, depreciation and amortization for the three and nine months ended September 30, 2018 , except for capital expenditures. See Note 7 - Equity Method Investments for additional information regarding our equity method investments. (2) No activity prior to September 14, 2018, the DGE acquisition date. (3) Includes elimination of proportionate consolidation amounts recorded for KTIPI to reconcile to (Gain) loss on equity method investments, net as reported in the consolidated statements of operations. (4) Interest expense is recorded based on actual third-party and intercompany debt agreements. Capitalized interest is recorded on the business unit where the assets reside. Nine Months Ended September 30, 2019 2018 (In thousands) Consolidated capital expenditures: Consolidated Statements of Cash Flows - Investing activities: Oil and gas assets $ 240,642 $ 149,305 Other property 8,291 3,560 Adjustments: Changes in capital accruals 11,083 13,965 Exploration expense, excluding unsuccessful well costs(1) 75,661 131,964 Capitalized interest (21,330 ) (21,209 ) Proceeds on sale of assets — (13,703 ) Other 3,959 111 Total consolidated capital expenditures $ 318,306 $ 263,993 ______________________________________ (1) Unsuccessful well costs are included in oil and gas assets when incurred.

Organization (Details)

Organization (Details)	9 Months Ended
	Sep. 30, 2019segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments	4

Accounting Policies (Details)

Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash, Cash Equivalents and Restricted Cash
Cash and cash equivalents	$ 203,646		$ 203,646			$ 173,515
Restricted cash - current	7,745		7,745			4,527
Restricted cash - long-term	3,667		3,667			7,574
Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows	215,058	$ 207,495	215,058	$ 207,495		185,616	$ 304,986
Inventories
Materials and supplies inventory	123,600		123,600			83,400
Hydrocarbons inventory	16,600		16,600			$ 1,400
Leases
Other assets (right-of-use assets)	20,436		20,436
Total lease liabilities	$ 23,774		$ 23,774
Accounting Standards Update 2016-02
Leases
Other assets (right-of-use assets)					$ 21,700
Total lease liabilities					$ 21,700
Phillips 66 Company | Sales Revenue, Net | Customer Concentration Risk
Risks and Uncertainties
Concentration risk, percentage	21.00%	6.00%	22.00%	3.00%
Shell Trading (US) Company | Sales Revenue, Net | Customer Concentration Risk
Risks and Uncertainties
Concentration risk, percentage	11.00%	3.00%	9.00%	1.00%

Accounting Policies - Summary o

Accounting Policies - Summary of Oil and Gas Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Provisional oil sales contracts	$ 31,683	$ (54,267)	$ (34,003)	$ (232,057)
Oil and gas revenue	357,036	242,833	1,049,759	585,220
Oil and gas revenue
Disaggregation of Revenue [Line Items]
Provisional oil sales contracts	4,668	3,075	1,881	3,584
Oil and gas revenue	357,036	242,833	1,049,759	585,220
Equatorial Guinea
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	54,894	0	207,173	0
Ghana
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	173,613	215,581	502,413	557,459
Gulf of Mexico
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 123,861	$ 24,177	$ 338,292	$ 24,177

Acquisitions and Divestitures (

Acquisitions and Divestitures (Details) $ in Thousands

1 Months Ended

3 Months Ended

9 Months Ended

Sep. 30, 2019km²meter

May 31, 2019

Mar. 31, 2019km²

Oct. 31, 2018company

Sep. 30, 2018USD ($)

Aug. 31, 2018USD ($)km²sub_periodblock

Jun. 30, 2018km²

Mar. 31, 2018km²block

Sep. 30, 2019USD ($)km²meterblock

Mar. 31, 2019km²sub_periodblock

Sep. 30, 2018USD ($)

Sep. 30, 2019USD ($)km²meter

Sep. 30, 2018USD ($)

Acquisitions and Divestitures

Gain on sale of assets | $

$ 0

$ 7,666

$ 0

$ 7,666

Number of companies in alliance | company

2

Deep Gulf Energy, LP

Acquisitions and Divestitures

Total purchase price | $

$ 1,275,000

Cash consideration | $

952,600

Transaction related costs | $

14,900

Deep Gulf Energy, LP | Common Shares

Acquisitions and Divestitures

Equity consideration | $

$ 307,900

Marine XXI Block | Petroleum Agreement

Acquisitions and Divestitures

Participating interests

85.00%

Area of petroleum exploration

2,350

2,350

Exploration period

4 years

3D seismic requirements

2,200

Number of sub-periods | sub_period

2

First sub exploration period

3 years

Marine XXI Block | Petroleum Agreement | SNPC

Acquisitions and Divestitures

Carried participating interest percentage

15.00%

15.00%

Percentage converted from carried to participating

15.00%

15.00%

U.S. Gulf Of Mexico Garden Banks Blocks | Farm-in agreement

Acquisitions and Divestitures

Number of blocks | block

18

U.S. Gulf Of Mexico Blocks | Farm-in agreement

Acquisitions and Divestitures

Number of blocks | block

3

U.S. Gulf Of Mexico Lease Sale 252 Blocks

Acquisitions and Divestitures

Number of blocks | block

9

U.S. Gulf Of Mexico Lease Sale 253 Blocks

Acquisitions and Divestitures

Number of blocks | block

4

Northern Cape Ultra Deep Block | Farm-in agreement

Acquisitions and Divestitures

Area of petroleum exploration

6,930

6,930

6,930

Exploration period

2 years

Participation interest acquired

45.00%

Northern Cape Ultra Deep Block | Farm-in agreement | Minimum

Acquisitions and Divestitures

Water depths | meter

2,500

2,500

2,500

Northern Cape Ultra Deep Block | Farm-in agreement | Maximum

Acquisitions and Divestitures

Water depths | meter

3,100

3,100

3,100

Block 6

Acquisitions and Divestitures

Participating interests

25.00%

Block 6 | Farm out agreement | Shell Sao Tome and Principe B.V.

Acquisitions and Divestitures

Participation interest acquired

20.00%

Block 11

Acquisitions and Divestitures

Participating interests

35.00%

Block 11 | Farm out agreement | Shell Sao Tome and Principe B.V.

Acquisitions and Divestitures

Participating interests

30.00%

Blocks 10 and 13 | Petroleum Agreement

Acquisitions and Divestitures

Participating interests

35.00%

Area of petroleum exploration

13,600

Exploration period

4 years

3D seismic requirements

13,500

First sub exploration period

4 years

Number of blocks | block

2

Blocks 10 and 13 | Petroleum Agreement | BP

Acquisitions and Divestitures

Participating interests

50.00%

Blocks 10 and 13 | Petroleum Agreement | ANP STP

Acquisitions and Divestitures

Carried participating interest percentage

15.00%

Block EG-24 | Farm-in agreement

Acquisitions and Divestitures

Area of petroleum exploration

3,500

Exploration period

3 years

3D seismic requirements

3,000

First sub exploration period

4 years

Participation interest acquired

80.00%

40.00%

Block EG-24 | Farm-in agreement | GEPetrol

Acquisitions and Divestitures

Carried participating interest percentage

20.00%

20.00%

Percentage converted from carried to participating

20.00%

20.00%

Blocks EG-21, S and W | Petroleum Agreement

Acquisitions and Divestitures

Area of petroleum exploration

6,000

Exploration period

5 years

3D seismic requirements

6,000

Number of sub-periods | sub_period

2

First sub exploration period

3 years

Number of blocks | block

3

Second sub exploration period

2 years

Blocks EG-21, S and W | Petroleum Agreement | GEPetrol

Acquisitions and Divestitures

Carried participating interest percentage

20.00%

Percentage converted from carried to participating

20.00%

Blocks EG-21, S and W | Farm out agreement

Acquisitions and Divestitures

Participating interests

40.00%

Gain on sale of assets | $

$ 7,700

Blocks EG-21, S and W | Farm out agreement | Trident

Acquisitions and Divestitures

Participation interest acquired

40.00%

Joint Interest Billings, Rela_2

Joint Interest Billings, Related Party Receivables and Notes Receivables (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Feb. 28, 2019USD ($)Agreement	Dec. 31, 2014	Sep. 30, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017
Joint interest billings
Joint interest billings, net			$ 54,409	$ 64,572
Long-term receivables			36,957	19,002
Related party receivable			0	$ 5,580
Kosmos-Trident International Petroleum Inc.
Joint interest billings
Ownership percentage					50.00%
Trident | Kosmos-Trident International Petroleum Inc.
Joint interest billings
Ownership percentage				50.00%
TEN Discoveries | GNPC
Joint interest billings
Joint interest billings, net			14,000	$ 14,000
Long-term receivables			17,200	14,000
TEN Discoveries | GNPC
Joint interest billings
GNPC's paying interest		5.00%
Kosmos-Trident International Petroleum Inc.
Joint interest billings
Related party receivable				$ 5,600
Carry Advance Agreements | National Oil Companies Of Mauritania And Senegal
Joint interest billings
Long-term receivables			$ 19,800
Number of agreements | Agreement	2
Share of development costs to be financed, up to	$ 239,700

Property and Equipment (Details

Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Oil and gas properties:
Proved properties	$ 4,827,304		$ 4,827,304		$ 4,236,489
Unproved properties	898,855		898,855		759,472
Total oil and gas properties	5,726,159		5,726,159		4,995,961
Accumulated depletion	(1,945,170)		(1,945,170)		(1,551,097)
Oil and gas properties, net	3,780,989		3,780,989		3,444,864
Other property	59,515		59,515		51,987
Accumulated depreciation	(41,468)		(41,468)		(37,150)
Other property, net	18,047		18,047		14,837
Property and equipment, net	3,799,036	$ 3,509,537	3,799,036	$ 3,509,537	$ 3,459,701
Depletion expense	$ 139,100	$ 76,800	$ 394,100	$ 199,700

Suspended Well Costs - Summary

Suspended Well Costs - Summary of Suspended Well Costs (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019USD ($)	Sep. 30, 2019USD ($)project	Dec. 31, 2018USD ($)project
Oil and Gas Exploration and Production Industries Disclosures [Abstract]
Capitalized exploratory well costs subsequently expensed in the same period	$ 1,400
Reconciliation of capitalized exploratory well costs on completed wells
Beginning balance	367,665
Additions to capitalized exploratory well costs pending the determination of proved reserves	55,244
Reclassification due to determination of proved reserves	(10,711)
Capitalized exploratory well costs charged to expense	0
Ending balance	412,198
Aging of capitalized exploratory well costs and number of projects for which exploratory well costs were capitalized for more than one year
Exploratory well costs capitalized for a period of one year or less		$ 0	$ 0
Exploratory well costs capitalized for a period of one to two years		77,995	299,253
Exploratory well costs capitalized for a period of three years or greater		334,203	68,412
Ending balance	$ 412,198	$ 412,198	$ 367,665
Number of projects that have exploratory well costs that have been capitalized for a period greater than one year | project		3	3

Suspended Well Costs - Narrativ

Suspended Well Costs - Narrative (Details)	May 31, 2015project
Greater Tortue Discovery
Capitalized Contract Cost [Line Items]
Number of additional appraisal wells drilled	3

Equity Method Investments - Nar

Equity Method Investments - Narrative (Details)	Jan. 01, 2019	Dec. 31, 2018	Dec. 31, 2017
Kosmos-Trident International Petroleum Inc.
Schedule of Equity Method Investments [Line Items]
Ownership percentage			50.00%
Basis presented		100.00%
Ceiba Field And Okume Complex Acquisition
Schedule of Equity Method Investments [Line Items]
Direct ownership percentage	40.375%

Equity Method Investments - Sum

Equity Method Investments - Summary of Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Costs and expenses:
Equity in earnings - KTIPI	$ 0	$ 24,841	$ 0	$ 59,637
Kosmos-Trident International Petroleum Inc.
Assets
Total current assets					$ 149,950
Property and equipment, net					271,627
Other assets					21
Total assets					421,598
Liabilities and stockholders' equity
Total current liabilities					226,311
Total long-term liabilities					536,178
Shareholders' equity:
Total shareholders' equity					(340,891)
Total liabilities and shareholders' equity					$ 421,598
Revenues and other income:
Oil and gas revenue		215,408		600,158
Other income		(72)		44
Total revenues and other income		215,336		600,202
Costs and expenses:
Oil and gas production		40,334		115,366
Depletion, depreciation and amortization		33,044		108,996
Other expenses, net		(58)		(211)
Total costs and expenses		73,320		224,151
Income before income taxes		142,016		376,051
Income tax expense		50,796		134,047
Net income		91,220		242,004
Kosmos' share of net income		45,610		121,002
Basis difference amortization		20,769		61,365
Equity in earnings - KTIPI		$ 24,841		$ 59,637

Equity Method Investments - Ass

Equity Method Investments - Asset Acquisition (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Sep. 30, 2019	Dec. 31, 2018
Liabilities assumed:
Asset retirement obligations		$ 9,706
Carrying value:
Equity method investment carrying value at December 31, 2018		$ 0	$ 51,896
Ceiba Field And Okume Complex Acquisition
Schedule of Equity Method Investments [Line Items]
Direct ownership percentage	40.375%
Assets acquired:
Proved oil and gas properties	$ 372,144
Unproved oil and gas properties	103,909
Prepaids and other	7,273
Total assets acquired	483,326
Liabilities assumed:
Asset retirement obligations	114,395
Deferred tax liabilities	247,636
Accrued liabilities and other	69,399
Total liabilities assumed	$ 431,430

Debt - Schedule of Instruments

Debt - Schedule of Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt
Outstanding debt principal	$ 2,150,000	$ 2,175,000
Unamortized issuance costs and discount	(43,798)	(54,453)
Long-term debt, net	2,106,202	2,120,547
The Facility | Revolving Credit Facility
Debt
Outstanding debt principal	1,500,000	1,325,000
Unamortized issuance costs and discount	(34,400)	(40,500)
Corporate Revolver | Revolving Credit Facility
Debt
Outstanding debt principal	0	325,000
7.125% Senior Notes due 2026 | Senior Notes
Debt
Outstanding debt principal	650,000	0
Unamortized issuance costs and discount	(9,400)
7.875% senior notes due 2021 | Senior Notes
Debt
Outstanding debt principal	$ 0	525,000
Unamortized issuance costs and discount		$ (14,000)

Debt - Facility (Details)

Debt - Facility (Details) - USD ($)	1 Months Ended		3 Months Ended		9 Months Ended
	Apr. 30, 2019	Feb. 28, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Mar. 31, 2019
Debt Instrument [Line Items]
Loss on extinguishment of debt			$ 0	$ 268,000	$ 24,794,000	$ 4,324,000
The Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Total commitment	$ 1,600,000,000	$ 1,500,000,000					$ 1,700,000,000
Additional commitments		500,000,000
Loss on extinguishment of debt		$ 4,100,000
Net deferred financing costs			34,400,000		34,400,000
Undrawn availability			100,000,000		100,000,000
Commitment reduction	$ 100,000,000
Availability period of revolving-credit		1 month
Amount outstanding under letters of credit			$ 0		$ 0

Debt - Corporate Revolver (Deta

Debt - Corporate Revolver (Details) - USD ($)	1 Months Ended
	Aug. 31, 2018	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Net deferred financing costs		$ 6,975,000	$ 8,937,000
Corporate Revolver | Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 400,000,000
Change in basis points	1.00%
Applicable margin	5.00%
Commitment fee percentage	30.00%
Undrawn availability		400,000,000
Net deferred financing costs		$ 7,000,000

Debt - Revolving Letter of Cred

Debt - Revolving Letter of Credit Facility (Details) $ in Millions	Sep. 30, 2019USD ($)letter_of_credit
Revolving Letter of Credit Facility
Debt Instrument [Line Items]
Number of letters of credit | letter_of_credit	6
Amount outstanding | $	$ 9.4
Letter of Credit Arrangement
Debt Instrument [Line Items]
Number of letters of credit | letter_of_credit	2
Amount outstanding | $	$ 20.4

Debt - 7.875% Senior Secured No

Debt - 7.875% Senior Secured Notes due 2021 (Details) - USD ($)	1 Months Ended			3 Months Ended		9 Months Ended
	Apr. 30, 2019	Apr. 30, 2015	Aug. 31, 2014	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Loss on extinguishment of debt				$ 0	$ 268,000	$ 24,794,000	$ 4,324,000
Senior Notes | 7.875% senior notes due 2021
Debt Instrument [Line Items]
Interest rate			7.875%
Senior notes offering face amount		$ 225,000,000	$ 300,000,000
Proceeds, net of offering discounts and deferred financing costs		$ 206,800,000	$ 292,500,000
Debt redeemed	$ 543,800,000
Loss on extinguishment of debt	$ 22,900,000

Debt - 7.125% Senior Notes due

Debt - 7.125% Senior Notes due 2026 (Details) - Senior Notes - 7.125% Senior Notes due 2026	1 Months Ended
	Apr. 30, 2019USD ($)
Debt Instrument [Line Items]
Interest rate	7.125%
Senior notes offering face amount	$ 650,000,000
Net proceeds from debt	$ 640,000,000
Redemption price percentage following change of control	101.00%
Redemption price percentage following sell of certain assets	100.00%
Any time prior to April 4, 2022
Debt Instrument [Line Items]
Maximum percentage of principal amount available to be redeemed with proceeds from equity offerings	40.00%
Debt Instrument Redemption Price Percentage With Proceeds From Equity Offerings	107.10%
Any time prior to April 4, 2022 with make-whole premium
Debt Instrument [Line Items]
Redemption price, as percent of the principal amount	100.00%
On or after April 4, 2022, but before April 4, 2023
Debt Instrument [Line Items]
Redemption price, as percent of the principal amount	103.60%
On or after April 4, 2023, but before April 4, 2024
Debt Instrument [Line Items]
Redemption price, as percent of the principal amount	101.80%
On or after April 4, 2024 and thereafter
Debt Instrument [Line Items]
Redemption price, as percent of the principal amount	100.00%

Debt - Maturities (Details)

Debt - Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Scheduled maturities of debt during the five year period and thereafter
Total	$ 2,150,000	$ 2,175,000
2019	0
2020	0
2021	274,800
2022	284,200
2023	271,600
Thereafter	1,319,400
Senior Notes | 7.125% Senior Notes due 2026
Scheduled maturities of debt during the five year period and thereafter
Total	$ 650,000	$ 0

Debt - Interest and other finan

Debt - Interest and other financing costs, net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Debt Disclosure [Abstract]
Interest expense	$ 34,944	$ 27,317	$ 111,566	$ 77,121
Amortization—deferred financing costs	2,285	2,346	6,974	7,069
Loss on extinguishment of debt	0	268	24,794	4,324
Capitalized interest	(7,077)	(7,097)	(21,330)	(21,209)
Deferred interest	290	(194)	1,559	(1,284)
Interest income	(972)	(788)	(2,215)	(2,579)
Other, net	1,251	1,697	4,217	4,671
Interest and other financing costs, net	$ 30,721	$ 23,549	$ 125,565	$ 68,113

Derivative Financial Instrume_3

Derivative Financial Instruments - Schedule of oil derivative contracts (Details)	9 Months Ended
	Sep. 30, 2019$ / bblMBbls
Dated Brent | Term October 2019 To December 2019 | Three-way collars
Derivative Financial Instruments
Volume (mbbls) | MBbls	2,628
Weighted Average Price Per Bbl [Abstract]
Net Deferred Premium Payable/(Receivable)	1.17
Swap (usd per bbl)	0
Sold Put (usd per bbl)	43.81
Floor (usd per bbl)	53.33
Ceiling (usd per bbl)	73.57
Dated Brent | Term October 2019 To December 2019 | Sold calls
Derivative Financial Instruments
Volume (mbbls) | MBbls	230
Weighted Average Price Per Bbl [Abstract]
Net Deferred Premium Payable/(Receivable)	0
Swap (usd per bbl)	0
Sold Put (usd per bbl)	0
Floor (usd per bbl)	0
Ceiling (usd per bbl)	80
Dated Brent | Term January 2020 To December 2020 | Three-way collars
Derivative Financial Instruments
Volume (mbbls) | MBbls	6,000
Weighted Average Price Per Bbl [Abstract]
Net Deferred Premium Payable/(Receivable)	0.45
Swap (usd per bbl)	0
Sold Put (usd per bbl)	45
Floor (usd per bbl)	57.50
Ceiling (usd per bbl)	80.18
Dated Brent | Term January 2020 To December 2020 | Swaps with sold puts
Derivative Financial Instruments
Volume (mbbls) | MBbls	2,000
Weighted Average Price Per Bbl [Abstract]
Net Deferred Premium Payable/(Receivable)	0
Swap (usd per bbl)	60.53
Sold Put (usd per bbl)	48.75
Floor (usd per bbl)	0
Ceiling (usd per bbl)	0
Dated Brent | Term January 2020 To December 2020 | Put spread
Derivative Financial Instruments
Volume (mbbls) | MBbls	2,000
Weighted Average Price Per Bbl [Abstract]
Net Deferred Premium Payable/(Receivable)	2.59
Swap (usd per bbl)	0
Sold Put (usd per bbl)	50
Floor (usd per bbl)	60
Ceiling (usd per bbl)	0
Dated Brent | Term January 2020 To December 2020 | Sold calls
Derivative Financial Instruments
Volume (mbbls) | MBbls	8,000
Weighted Average Price Per Bbl [Abstract]
Net Deferred Premium Payable/(Receivable)	1.17
Swap (usd per bbl)	0
Sold Put (usd per bbl)	0
Floor (usd per bbl)	0
Ceiling (usd per bbl)	85
Dated Brent | Term January 2021 To December 2021 | Sold calls
Derivative Financial Instruments
Volume (mbbls) | MBbls	1,000
Weighted Average Price Per Bbl [Abstract]
Net Deferred Premium Payable/(Receivable)	0
Swap (usd per bbl)	0
Sold Put (usd per bbl)	0
Floor (usd per bbl)	0
Ceiling (usd per bbl)	75
NYMEX WTI | Term October 2019 To December 2019 | Swaps
Derivative Financial Instruments
Volume (mbbls) | MBbls	265
Weighted Average Price Per Bbl [Abstract]
Net Deferred Premium Payable/(Receivable)	0
Swap (usd per bbl)	51.61
Sold Put (usd per bbl)	0
Floor (usd per bbl)	0
Ceiling (usd per bbl)	0
Argus LLS | Term October 2019 To December 2019 | Collars
Derivative Financial Instruments
Volume (mbbls) | MBbls	250
Weighted Average Price Per Bbl [Abstract]
Net Deferred Premium Payable/(Receivable)	0
Swap (usd per bbl)	0
Sold Put (usd per bbl)	0
Floor (usd per bbl)	60
Ceiling (usd per bbl)	88.75

Derivative Financial Instrume_4

Derivative Financial Instruments - Narrative (Details) - Dated Brent	1 Months Ended	9 Months Ended
	Oct. 31, 2019$ / bblMBbls	Sep. 30, 2019$ / bblMBbls
Put Option | Term January 2020 To December 2020
Derivative Financial Instruments
Volume (mbbls) | MBbls		2,000
Floor (usd per bbl)		60
Sold Put (usd per bbl)		50
Ceiling (usd per bbl)		0
Sold calls | Term January 2020 To December 2020
Derivative Financial Instruments
Volume (mbbls) | MBbls		8,000
Floor (usd per bbl)		0
Sold Put (usd per bbl)		0
Ceiling (usd per bbl)		85
Sold calls | Term January 2021 To December 2021
Derivative Financial Instruments
Volume (mbbls) | MBbls		1,000
Floor (usd per bbl)		0
Sold Put (usd per bbl)		0
Ceiling (usd per bbl)		75
Subsequent Event | Put Option | Term January 2020 To December 2020
Derivative Financial Instruments
Volume (mbbls) | MBbls	2,000
Floor (usd per bbl)	57.50
Sold Put (usd per bbl)	50
Subsequent Event | Sold calls | Term January 2021 To December 2021
Derivative Financial Instruments
Volume (mbbls) | MBbls	3,000
Ceiling (usd per bbl)	71.67

Derivative Financial Instrume_5

Derivative Financial Instruments - Derivatives instrument and gain/loss from derivatives (Details) - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Derivative instruments, Balance Sheet Location
Derivatives assets—current	$ 22,067,000	$ 38,785,000
Derivatives assets—long-term	10,535,000	14,312,000
Derivatives liabilities—current	(8,461,000)	(12,172,000)
Derivatives liabilities—long-term	(2,699,000)	(10,181,000)
Derivatives not designated as hedging instruments:
Derivative instruments, Balance Sheet Location
Total derivatives not designated as hedging instruments	21,442,000	30,744,000
Derivatives not designated as hedging instruments: | Commodity
Derivative instruments, Balance Sheet Location
Derivatives assets—current	22,067,000	38,785,000
Derivatives assets—long-term	10,535,000	14,312,000
Derivatives liabilities—current	(8,461,000)	(12,172,000)
Derivatives liabilities—long-term	(2,699,000)	(10,181,000)
Net deferred premiums payable related to commodity derivative contracts - current assets	4,100,000	1,600,000
Net deferred premiums payable related to commodity derivative contracts - non-current assets	2,600,000	1,300,000
Net deferred premiums payable related to commodity derivative contracts - current liabilities	6,500,000	18,000,000
Net deferred premiums payable related to commodity derivative contracts - non-current liabilities	0	500,000
Oil and gas revenue | Derivatives not designated as hedging instruments: | Commodity
Derivative instruments, Balance Sheet Location
Derivatives assets—current	$ 0	$ 400,000

Derivative Financial Instrume_6

Derivative Financial Instruments - Schedule of derivative instruments by location of gain/(loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative instruments, Location of Gain/(Loss)
Amount of Gain/(Loss)	$ 31,683	$ (54,267)	$ (34,003)	$ (232,057)
Commodity | Oil and gas revenue
Derivative instruments, Location of Gain/(Loss)
Amount of Gain/(Loss)	4,667	3,075	1,881	3,584
Commodity | Derivatives, net
Derivative instruments, Location of Gain/(Loss)
Amount of Gain/(Loss)	27,016	(57,357)	(35,884)	(236,107)
Interest rate | Interest expense
Derivative instruments, Location of Gain/(Loss)
Amount of Gain/(Loss)	$ 0	$ 15	$ 0	$ 466

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Carrying Value
Liabilities:
Long-term debt	$ 2,142,318	$ 2,161,873
Fair Value
Liabilities:
Long-term debt	2,170,514	2,175,026
7.125% Senior Notes due 2026 | Senior Notes | Carrying Value
Liabilities:
Long-term debt	642,318	0
7.125% Senior Notes due 2026 | Senior Notes | Fair Value
Liabilities:
Long-term debt	670,514	0
7.875% senior notes due 2021 | Senior Notes | Carrying Value
Liabilities:
Long-term debt	0	511,873
7.875% senior notes due 2021 | Senior Notes | Fair Value
Liabilities:
Long-term debt	0	525,026
Corporate Revolver | Facility | Carrying Value
Liabilities:
Long-term debt	0	325,000
Corporate Revolver | Facility | Fair Value
Liabilities:
Long-term debt	0	325,000
The Facility | Facility | Carrying Value
Liabilities:
Long-term debt	1,500,000	1,325,000
The Facility | Facility | Fair Value
Liabilities:
Long-term debt	1,500,000	1,325,000
Recurring basis
Liabilities:
Total fair value, net	21,442	30,744
Recurring basis | Commodity
Assets:
Derivative asset, fair value	32,602	53,097
Liabilities:
Derivative liability, fair value	(11,160)	(22,353)
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Liabilities:
Total fair value, net	0	0
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Commodity
Assets:
Derivative asset, fair value	0	0
Liabilities:
Derivative liability, fair value	0	0
Recurring basis | Significant Other Observable Inputs (Level 2)
Liabilities:
Total fair value, net	21,442	30,744
Recurring basis | Significant Other Observable Inputs (Level 2) | Commodity
Assets:
Derivative asset, fair value	32,602	53,097
Liabilities:
Derivative liability, fair value	(11,160)	(22,353)
Recurring basis | Significant Unobservable Inputs (Level 3)
Liabilities:
Total fair value, net	0	0
Recurring basis | Significant Unobservable Inputs (Level 3) | Commodity
Assets:
Derivative asset, fair value	0	0
Liabilities:
Derivative liability, fair value	$ 0	$ 0

Equity-based Compensation - Add

Equity-based Compensation - Additional Information (Details) - LTIP - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognized		$ 9.5	$ 8.9	$ 27.4	$ 26
Tax benefit		3.1	1.6	5.9	5
Net tax shortfall (windfall) related to equity-based compensation		0	0.1	1.2	(0.3)
Fair value of awards vested		$ 0.7	$ 1.1	$ 14.7	$ 83.1
Vesting period				3 years
Number of additional shares authorized (in shares)	11,000,000
Number of shares authorized (in shares)		50,500,000		50,500,000
Number of shares remaining available for grant (in shares)		9,800,000		9,800,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense not yet recognized		$ 38.3		$ 38.3
Weighted average period over which compensation expense is to be recognized				1 year 11 months 19 days
Market/Service Vesting Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value of awards granted (in dollars per share)				$ 6.02
Market/Service Vesting Restricted Stock Units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of the awards granted (up to)				0.00%
Grant date fair value of awards granted (in dollars per share)				$ 4.83
Expected volatility				44.00%
Risk-free interest rate				0.80%
Market/Service Vesting Restricted Stock Units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of the awards granted (up to)				200.00%
Grant date fair value of awards granted (in dollars per share)				$ 12.96
Expected volatility				52.00%
Risk-free interest rate				2.50%

Equity-based Compensation - Sch

Equity-based Compensation - Schedule of awards (Details) - LTIP shares in Thousands	9 Months Ended
	Sep. 30, 2019$ / sharesshares
Service Vesting Restricted Stock Units
Outstanding unvested awards activity
Outstanding at the beginning of the period (in shares) | shares	4,115
Granted (in shares) | shares	3,096
Forfeited (in shares) | shares	(134)
Vested (in shares) | shares	(1,999)
Outstanding at the end of the period (in shares) | shares	5,078
Weighted-Average Grant-Date Fair Value
Outstanding at beginning of the period (in dollars per share)	$ 6.42
Granted (in dollars per share)	4.96
Forfeited (in dollars per share)	6.11
Vested (in dollars per share)	5.92
Outstanding at the end of the period (in dollars per share)	$ 5.73
Market/Service Vesting Restricted Stock Units
Outstanding unvested awards activity
Outstanding at the beginning of the period (in shares) | shares	6,716
Granted (in shares) | shares	3,160
Forfeited (in shares) | shares	(295)
Vested (in shares) | shares	(1,300)
Outstanding at the end of the period (in shares) | shares	8,281
Weighted-Average Grant-Date Fair Value
Outstanding at beginning of the period (in dollars per share)	$ 9.02
Granted (in dollars per share)	6.02
Forfeited (in dollars per share)	9.87
Vested (in dollars per share)	6.32
Outstanding at the end of the period (in dollars per share)	8.39
Minimum | Market/Service Vesting Restricted Stock Units
Weighted-Average Grant-Date Fair Value
Granted (in dollars per share)	$ 4.83
Vesting percentage of the awards granted	0.00%
Maximum | Market/Service Vesting Restricted Stock Units
Weighted-Average Grant-Date Fair Value
Granted (in dollars per share)	$ 12.96
Vesting percentage of the awards granted	200.00%

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Taxes
Effective tax rate (as a percent)	59.00%	10.00%	173.00%	17.00%
Income (loss) before income taxes	$ 39,535	$ (114,693)	$ 27,394	$ (337,885)
Uncertain tax positions	0		0
United States
Income Taxes
Income (loss) before income taxes	3,464	(53,136)	(70,776)	(49,967)
Bermuda
Income Taxes
Income (loss) before income taxes	0	(15,513)	$ 0	(47,474)
Foreign—other
Income Taxes
Effective tax rate (as a percent)			0.00%
Statutory tax rate (as a percent)			0.00%
Income (loss) before income taxes	$ 36,071	$ (46,044)	$ 98,170	$ (240,444)

Net Income (Loss) Per Share (De

Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Numerator:
Net (loss) income	$ 16,065	$ 16,837	$ (52,906)	$ (126,057)	$ (103,273)	$ (50,226)	$ (20,004)	$ (279,556)
Weighted average number of shares outstanding:
Basic (in shares)	401,466			404,536			401,319	399,026
Restricted stock units (in shares)	9,526			0			0	0
Diluted (in shares)	410,992			404,536			401,319	399,026
Net income (loss) per share:
Basic (in dollars per share)	$ 0.04			$ (0.31)			$ (0.05)	$ (0.70)
Diluted (in dollars per share)	$ 0.04			$ (0.31)			$ (0.05)	$ (0.70)
Outstanding restricted stock awards and units excluded from the computations of diluted net income per share (in shares)	700			13,100			15,400	14,500

Commitments and Contingencies_2

Commitments and Contingencies (Details)	Nov. 01, 2019$ / shares	Sep. 30, 2019USD ($)$ / shares	Jun. 30, 2019$ / shares	Mar. 31, 2019$ / shares	Sep. 30, 2018$ / shares	Sep. 30, 2019USD ($)km²meterexploration_well$ / shares	Sep. 30, 2018$ / shares	Dec. 31, 2018USD ($)
Commitments and contingencies
Dividends declared per common stock (in dollars per share) | $ / shares		$ 0.0452	$ 0.0452	$ 0.0452	$ 0	$ 0.1356	$ 0
SAO TOME AND PRINCIPE AND NAMIBIA
Commitments and contingencies
Number of exploration wells | exploration_well						1
Sao Tome and Principe
Commitments and contingencies
3D seismic requirements | km²						13,500
Namibia
Commitments and contingencies
Number of exploration wells | exploration_well						1
Mauritania
Commitments and contingencies
Number of exploration wells | exploration_well						2
SOUTH AFRICA
Commitments and contingencies
2D seismic requirements | meter						500
Surety Bond | Gulf of Mexico
Commitments and contingencies
Cash collateral | $		$ 0				$ 0		$ 600,000
Bureau Of Ocean Energy Management | Surety Bond | Gulf of Mexico
Commitments and contingencies
Required performance bonds | $		208,700,000				208,700,000		200,900,000
Third Party | Surety Bond | Gulf of Mexico
Commitments and contingencies
Required performance bonds | $		$ 3,700,000				$ 3,700,000		$ 3,700,000
Subsequent Event
Commitments and contingencies
Dividends declared per common stock (in dollars per share) | $ / shares	$ 0.0452

Commitments and Contingencies -

Commitments and Contingencies - Leases (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019USD ($)	Sep. 30, 2019USD ($)
Lease, Cost [Abstract]
Operating lease cost	$ 1,279	$ 4,288
Short-term lease cost	960	1,547
Total lease cost	2,239	5,835
Balance sheet classifications
Other assets (right-of-use assets)	20,436	20,436
Accrued liabilities (current maturities of leases)	1,294	1,294
Other long-term liabilities (non-current maturities of leases)	$ 22,480	$ 22,480
Weighted average remaining lease term	9 years 1 month 6 days	9 years 1 month 6 days
Weighted average discount rate	9.80%	9.80%
Operating cash flows for operating leases		$ 3,077
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2019	$ 483	483
2020	4,098	4,098
2021	4,148	4,148
2022	4,199	4,199
2023	4,249	4,249
Thereafter	19,480	19,480
Total undiscounted lease payments	36,657	36,657
Less: Imputed interest	(12,883)	(12,883)
Total lease liabilities	$ 23,774	$ 23,774
Minimum
Lessee, Lease, Description [Line Items]
Operating lease, initial term	1 year	1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating lease, initial term	10 years	10 years

Additional Financial Informat_3

Additional Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Accrued liabilities:
Exploration, development and production	$ 114,833		$ 114,833		$ 92,613
Revenue payable	33,721		33,721		24,379
Current asset retirement obligations	5,844		5,844		6,617
Operating leases	1,294		1,294
General and administrative expenses	31,913		31,913		39,373
Interest	27,913		27,913		18,152
Income taxes	69,938		69,938		8,958
Taxes other than income	2,060		2,060		4,613
Derivatives	2,975		2,975		441
Other	1,928		1,928		450
Accrued liabilities	292,419		292,419		$ 195,596
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning asset retirement obligations	290,370		290,370
Additions associated with Equatorial Guinea - Ceiba Field and Okume Complex			114,395
Liabilities incurred during period			9,706
Liabilities settled during period			(4,384)
Revisions in estimated retirement obligations			905
Accretion expense			17,795
Ending asset retirement obligations			151,953
Facilities insurance modifications, expenditures	12,600	$ 12,300	34,800	$ 31,500
Facilities insurance modifications, insurance recoveries			40,000	9,700
Other Expenses, Net
(Gain) loss on disposal of inventory	1,232	(2)	1,419	(26)
(Gain) loss on ARO liability settlements	(746)	0	1,167	0
Disputed charges and related costs, net of recoveries	1,677	(12,682)	1,663	(9,721)
Other, net	9,309	(123)	7,549	1,583
Other expenses, net	$ 11,472	(12,807)	$ 11,798	$ (8,164)
Payment of tax settlements		$ 8,700

Business Segment Information (D

Business Segment Information (Details) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Sep. 30, 2019USD ($)segment	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment							4
Oil and gas revenue	$ 357,036			$ 242,833			$ 1,049,759	$ 585,220
Gain on sale of assets	0			7,666			0	7,666
Other income, net	(66)			(280)			(65)	(17)
Total revenues and other income	356,970			250,219			1,049,694	592,869
Oil and gas production	95,540			55,078			266,316	151,661
Facilities insurance modifications, net	12,569			12,334			(5,174)	21,812
Exploration expenses	22,773			148,238			83,022	246,912
General and administrative	24,723			25,963			88,703	65,343
Depletion, depreciation and amortization	146,653			80,041			416,186	208,607
Interest and other financing costs, net	30,721			23,549			125,565	68,113
Derivatives, net	(27,016)			57,357			35,884	236,107
Gain on equity method investments, net	0			(24,841)			0	(59,637)
Other expenses, net	11,472			(12,807)			11,798	(8,164)
Total costs and expenses	317,435			364,912			1,022,300	930,754
Income (loss) before income taxes	39,535			(114,693)			27,394	(337,885)
Income tax expense (benefit)	23,470			11,364			47,398	(58,329)
Net income (loss)	16,065	$ 16,837	$ (52,906)	(126,057)	$ (103,273)	$ (50,226)	(20,004)	(279,556)
Consolidated capital expenditures	107,393			109,191			318,306	263,993
Property and equipment, net	3,799,036			3,509,537			3,799,036	3,509,537	$ 3,459,701
Total assets	4,468,259			4,329,464			4,468,259	4,329,464	$ 4,088,189
Corporate & Other
Segment Reporting Information [Line Items]
Oil and gas revenue	0			0			0	0
Gain on sale of assets				0				0
Other income, net	5,706			78,166			97,594	315,771
Total revenues and other income	5,706			78,166			97,594	315,771
Oil and gas production	0			1,331			0	3,334
Facilities insurance modifications, net	0			0			0	0
Exploration expenses	8,369			22,457			32,174	98,392
General and administrative	38,897			42,072			127,416	122,558
Depletion, depreciation and amortization	913			1,037			2,941	3,111
Interest and other financing costs, net	17,304			7,704			77,782	24,735
Derivatives, net	(25,271)			47,275			7,116	226,025
Gain on equity method investments, net				0				0
Other expenses, net	1,253			846			1,304	2,695
Total costs and expenses	41,465			122,722			248,733	480,850
Income (loss) before income taxes	(35,759)			(44,556)			(151,139)	(165,079)
Income tax expense (benefit)	3,833			1,826			(15,466)	3,143
Net income (loss)	(39,592)			(46,382)			(135,673)	(168,222)
Consolidated capital expenditures	13,127			17,970			41,177	102,651
Property and equipment, net	43,281			34,551			43,281	34,551
Total assets	12,078,321			10,660,832			12,078,321	10,660,832
Eliminations
Segment Reporting Information [Line Items]
Oil and gas revenue	0			(107,704)			0	(300,079)
Gain on sale of assets				0				0
Other income, net	(5,973)			(78,129)			(98,120)	(315,793)
Total revenues and other income	(5,973)			(185,833)			(98,120)	(615,872)
Oil and gas production	0			(20,167)			0	(57,683)
Facilities insurance modifications, net	0			0			0	0
Exploration expenses	0			0			0	0
General and administrative	(29,459)			(29,078)			(85,653)	(84,288)
Depletion, depreciation and amortization	0			(37,291)			0	(115,862)
Interest and other financing costs, net	(1,784)			(1,784)			(5,351)	(5,351)
Derivatives, net	0			0			0	0
Gain on equity method investments, net				(24,841)				(59,637)
Other expenses, net	25,270			(47,274)			(7,116)	(226,027)
Total costs and expenses	(5,973)			(160,435)			(98,120)	(548,848)
Income (loss) before income taxes	0			(25,398)			0	(67,024)
Income tax expense (benefit)	0			(25,398)			0	(67,024)
Net income (loss)	0			0			0	0
Consolidated capital expenditures	0			0			0	0
Property and equipment, net	0			0			0	0
Total assets	(13,821,741)			(12,489,869)			(13,821,741)	(12,489,869)
Ghana | Operating Segments
Segment Reporting Information [Line Items]
Oil and gas revenue	177,797			218,656			502,800	561,043
Gain on sale of assets				0				0
Other income, net	1			0			2	(17)
Total revenues and other income	177,798			218,656			502,802	561,026
Oil and gas production	42,017			49,280			117,027	143,860
Facilities insurance modifications, net	12,569			12,334			(5,174)	21,812
Exploration expenses	82			57,818			189	58,076
General and administrative	3,886			5,786			15,844	15,651
Depletion, depreciation and amortization	73,347			70,799			204,108	197,260
Interest and other financing costs, net	16,821			21,989			56,500	65,357
Derivatives, net	0			0			0	0
Gain on equity method investments, net				0				0
Other expenses, net	(25,357)			34,610			6,761	216,319
Total costs and expenses	123,365			252,616			395,255	718,335
Income (loss) before income taxes	54,433			(33,960)			107,547	(157,309)
Income tax expense (benefit)	10,585			21,862			30,285	(49,148)
Net income (loss)	43,848			(55,822)			77,262	(108,161)
Consolidated capital expenditures	28,398			32,501			96,861	71,330
Property and equipment, net	1,603,170			1,727,595			1,603,170	1,727,595
Total assets	1,844,328			2,073,825			1,844,328	2,073,825
Equatorial Guinea | Operating Segments
Segment Reporting Information [Line Items]
Oil and gas revenue	55,378			107,704			208,667	300,079
Gain on sale of assets				7,666				7,666
Other income, net	0			(317)			0	22
Total revenues and other income	55,378			115,053			208,667	307,767
Oil and gas production	21,369			20,167			60,645	57,683
Facilities insurance modifications, net	0			0			0	0
Exploration expenses	2,437			16,584			8,080	33,665
General and administrative	1,719			1,761			5,303	3,768
Depletion, depreciation and amortization	16,019			37,291			55,323	115,862
Interest and other financing costs, net	0			(4)			0	(9)
Derivatives, net	0			0			0	0
Gain on equity method investments, net				0				0
Other expenses, net	615			(976)			(1,629)	(1,138)
Total costs and expenses	42,159			74,823			127,722	209,831
Income (loss) before income taxes	13,219			40,230			80,945	97,936
Income tax expense (benefit)	6,110			25,398			33,403	67,024
Net income (loss)	7,109			14,832			47,542	30,912
Consolidated capital expenditures	15,397			2,913			36,448	27,891
Property and equipment, net	460,044			3,801			460,044	3,801
Total assets	489,564			145,823			489,564	145,823
Mauritania And Senegal | Operating Segments
Segment Reporting Information [Line Items]
Oil and gas revenue	0			0			0	0
Gain on sale of assets				0				0
Other income, net	0			0			0	0
Total revenues and other income	0			0			0	0
Oil and gas production	0			0			0	0
Facilities insurance modifications, net	0			0			0	0
Exploration expenses	1,260			1,203			9,745	6,603
General and administrative	2,678			1,396			6,505	3,628
Depletion, depreciation and amortization	15			15			46	46
Interest and other financing costs, net	(6,703)			(6,441)			(20,020)	(18,704)
Derivatives, net	0			0			0	0
Gain on equity method investments, net				0				0
Other expenses, net	9,141			(13)			9,783	(13)
Total costs and expenses	6,391			(3,840)			6,059	(8,440)
Income (loss) before income taxes	(6,391)			3,840			(6,059)	8,440
Income tax expense (benefit)	0			0			0	0
Net income (loss)	(6,391)			3,840			(6,059)	8,440
Consolidated capital expenditures	842			3,319			7,132	9,633
Property and equipment, net	428,596			403,111			428,596	403,111
Total assets	568,743			465,352			568,743	465,352
U.S. Gulf of Mexico | Operating Segments
Segment Reporting Information [Line Items]
Oil and gas revenue	123,861			24,177			338,292	24,177
Gain on sale of assets				0				0
Other income, net	200			0			459	0
Total revenues and other income	124,061			24,177			338,751	24,177
Oil and gas production	32,154			4,467			88,644	4,467
Facilities insurance modifications, net	0			0			0	0
Exploration expenses	10,625			50,176			32,834	50,176
General and administrative	7,002			4,026			19,288	4,026
Depletion, depreciation and amortization	56,359			8,190			153,768	8,190
Interest and other financing costs, net	5,083			2,085			16,654	2,085
Derivatives, net	(1,745)			10,082			28,768	10,082
Gain on equity method investments, net				0				0
Other expenses, net	550			0			2,695	0
Total costs and expenses	110,028			79,026			342,651	79,026
Income (loss) before income taxes	14,033			(54,849)			(3,900)	(54,849)
Income tax expense (benefit)	2,942			(12,324)			(824)	(12,324)
Net income (loss)	11,091			(42,525)			(3,076)	(42,525)
Consolidated capital expenditures	49,629			52,488			136,688	52,488
Property and equipment, net	1,263,945			1,340,479			1,263,945	1,340,479
Total assets	$ 3,309,044			$ 3,473,501			$ 3,309,044	$ 3,473,501

Business Segment Information -

Business Segment Information - Consolidated Capital Expenditures (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting [Abstract]
Oil and gas assets			$ 240,642	$ 149,305
Other property			8,291	3,560
Changes in capital accruals			11,083	13,965
Exploration expense, excluding unsuccessful well costs			75,661	131,964
Capitalized interest			(21,330)	(21,209)
Proceeds on sale of assets			0	(13,703)
Other			3,959	111
Consolidated capital expenditures	$ (107,393)	$ (109,191)	$ (318,306)	$ (263,993)