Carrizo Oil & Gas (CRZO) 10-Q 9 May 17 2017 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2017	Apr. 28, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q1
Entity Registrant Name	CARRIZO OIL & GAS INC
Entity Central Index Key	1,040,593
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		65,807,064

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 2,391	$ 4,194
Accounts receivable, net	67,257	64,208
Derivative assets, current	1,036	1,237
Other current assets	2,542	3,349
Total current assets	73,226	72,988
Oil and gas properties, full cost method
Proved properties, net	1,371,335	1,294,667
Unproved properties, not being amortized	253,270	240,961
Other property and equipment, net	9,599	10,132
Total property and equipment, net	1,634,204	1,545,760
Deferred income tax assets, noncurrent	0	0
Derivative assets, noncurrent	0	0
Other assets	7,010	7,579
Total Assets	1,714,440	1,626,327
Current liabilities
Accounts payable	51,968	55,631
Revenues and royalties payable	44,038	38,107
Accrued capital expenditures	69,040	36,594
Accrued interest	20,957	22,016
Accrued Lease Operating Expense	11,919	12,377
Derivative liabilities	7,456	22,601
Deferred income tax liabilities, current	0	0
Other current liabilities	22,650	24,633
Total current liabilities	228,028	211,959
Long-term debt	1,362,046	1,325,418
Asset retirement obligations	21,737	20,848
Derivative liabilities, noncurrent	18,675	27,528
Other liabilities	14,027	17,116
Liabilities	1,644,513	1,602,869
Commitments and contingencies
Shareholders’ equity
Common stock, $0.01 par value, 90,000,000 shares authorized; 65,796,342 issued and outstanding as of March 31, 2017 and 65,132,499 issued and outstanding as of December 31, 2016	658	651
Additional paid-in capital	1,672,332	1,665,891
Accumulated deficit	(1,603,063)	(1,643,084)
Total shareholders’ equity	69,927	23,458
Total Liabilities and Shareholders’ Equity	$ 1,714,440	$ 1,626,327

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	90,000,000	90,000,000
Common stock, shares issued (in shares)	65,796,342	65,132,499
Common stock, shares outstanding (in shares)	65,796,342	65,132,499

Consolidated Statements Of Oper

Consolidated Statements Of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Crude oil revenues	$ 128,092	$ 67,996
Natural gas liquids revenues	7,425	3,440
Natural gas revenues	15,838	9,826
Total revenues	151,355	81,262
Costs and Expenses
Lease operating	29,845	23,675
Production taxes	6,208	3,431
Ad valorem taxes	2,967	2,070
Depreciation, depletion and amortization	54,382	59,577
General and administrative, net	21,703	21,303
(Gain) loss on derivatives, net	(25,316)	(10,553)
Interest expense, net	20,571	18,713
Impairment of proved oil and gas properties	0	274,413
Other (income) expense, net	974	(93)
Total Costs and Expenses	111,334	392,536
Income (Loss) Before Income Taxes	40,021	(311,274)
Income tax expense	0	(121)
Net Income (loss)	$ 40,021	$ (311,395)
Net Income (Loss) Per Common Share
Income (loss) per share, basic (in dollars per share)	$ 0.61	$ (5.34)
Income (loss) per share, diluted (in dollars per share)	$ 0.61	$ (5.34)
Weighted Average Common Shares Outstanding
Basic (in shares)	65,188	58,360
Diluted (in shares)	65,778	58,360

Consolidated Statements Of Shar

Consolidated Statements Of Shareholders' Equity - 3 months ended Mar. 31, 2017 - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings (Accumulated Deficit) [Member]
BALANCE at Dec. 31, 2016	$ 23,458	$ 651	$ 1,665,891	$ (1,643,084)
BALANCE, shares at Dec. 31, 2016		65,132,499
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	6,448		6,448
Issuance of common stock upon grants of restricted stock awards, net of forfeitures, and vestings of restricted stock units and performance shares	0	$ 7	(7)
Issuance of common stock upon grants of restricted stock awards, net of forfeitures, and vestings of restricted stock units and performance shares, shares		663,843
Net Income (loss)	40,021			40,021
BALANCE at Mar. 31, 2017	$ 69,927	$ 658	$ 1,672,332	$ (1,603,063)
BALANCE, shares at Mar. 31, 2017		65,796,342

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Net income (loss)	$ 40,021	$ (311,395)
Adjustments to reconcile income (loss) to net cash provided by operating activities
Depreciation, depletion and amortization	54,382	59,577
Impairment of proved oil and gas properties	0	274,413
(Gain) loss on derivatives, net	(25,316)	(10,553)
Cash received for derivative settlements, net	1,519	51,163
Stock-based compensation expense, net	2,014	11,522
Non-cash interest expense, net	1,091	1,160
Other, net	1,620	1,116
Changes in components of working capital and other assets and liabilities-
Accounts receivable	(2,749)	(2,065)
Accounts payable	6,661	(18,711)
Accrued liabilities	(2,154)	(1,667)
Other assets and liabilities, net	(681)	(692)
Net cash provided by operating activities	76,408	53,868
Cash Flows From Investing Activities
Capital expenditures - oil and gas properties	(123,749)	(125,989)
Acquisitions of oil and gas properties	(7,032)	0
Proceeds from sales of oil and gas properties, net	17,372	1,785
Other, net	(417)	(617)
Net cash used in investing activities	(113,826)	(124,821)
Cash Flows From Financing Activities
Borrowings under credit agreement	280,504	73,647
Repayments of borrowings under credit agreement	(244,504)	(43,097)
Payments of debt issuance costs	(50)	(50)
Other, net	(335)	(307)
Net cash provided by financing activities	35,615	30,193
Net Decrease in Cash and Cash Equivalents	(1,803)	(40,760)
Cash and Cash Equivalents, Beginning of Period	4,194	42,918
Cash and Cash Equivalents, End of Period	$ 2,391	$ 2,158

Nature Of Operations

Nature Of Operations	3 Months Ended
	Mar. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature Of Operations	1. Basis of Presentation Nature of Operations Carrizo Oil & Gas, Inc. is a Houston-based energy company which, together with its subsidiaries (collectively, the “Company”), is actively engaged in the exploration, development, and production of oil, NGLs, and gas primarily from resource plays located in the United States. The Company’s current operations are principally focused in proven, producing oil and gas plays primarily in the Eagle Ford Shale in South Texas, the Delaware Basin in West Texas, the Niobrara Formation in Colorado, the Utica Shale in Ohio, and the Marcellus Shale in Pennsylvania. Consolidated Financial Statements The accompanying unaudited interim consolidated financial statements include the accounts of the Company after elimination of intercompany transactions and balances and have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (the “SEC”) and therefore do not include all disclosures required for financial statements prepared in conformity with accounting principles generally accepted in the U.S. (“GAAP”). In the opinion of management, these financial statements include all adjustments (consisting of normal recurring accruals and adjustments) necessary to present fairly, in all material respects, the Company’s interim financial position, results of operations and cash flows. However, the results of operations for the periods presented are not necessarily indicative of the results of operations that may be expected for the full year. These financial statements and related notes included in this Quarterly Report on Form 10-Q should be read in conjunction with the Company’s audited Consolidated Financial Statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 (“ 2016 Annual Report”). Certain reclassifications have been made to prior period amounts to conform to the current period presentation. Such reclassifications had no material impact on prior period amounts.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	2. Summary of Significant Accounting Policies The Company has provided a discussion of significant accounting policies, estimates, and judgments in “Note 2. Summary of Significant Accounting Policies” of the Notes to Consolidated Financial Statements in its 2016 Annual Report. There have been no changes to the Company’s significant accounting policies since December 31, 2016 , other than the adoption of Accounting Standards Update No. 2016-09 described further below. Recently Adopted Accounting Pronouncement In March 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”), which amends certain aspects of accounting for share-based payment arrangements. ASU 2016-09 revises or provides alternative accounting for the tax impacts of share-based payment arrangements, forfeitures, minimum statutory tax withholdings, and prescribes certain disclosures to be made in the period of adoption. Effective January, 1, 2017, the Company adopted ASU 2016-09. Using the modified retrospective approach as prescribed by ASU 2016-09, the Company recognized previously unrecognized windfall tax benefits which resulted in a cumulative-effect adjustment to retained earnings of approximately $15.7 million . This adjustment increased deferred tax assets, which in turn increased the valuation allowance by the same amount as of the beginning of 2017, resulting in a net cumulative-effect adjustment to retained earnings of zero. As a result of adoption, on a prospective basis as prescribed by ASU 2016-09, all windfall tax benefits and tax shortfalls will be recorded as income tax expense or benefit in the consolidated statements of operations. As long as the Company continues to conclude that the valuation allowance against its net deferred tax assets is necessary, this portion of ASU 2016-09 will have no significant effect on the Company’s consolidated balance sheets or consolidated statements of operations. In addition, windfall tax benefits are now required to be presented in cash flows from operating activities in the consolidated statements of cash flows as compared to cash flows from financing activities, which the Company has elected to adopt prospectively. There are no periods presented that would require reclassification of cash flows had the Company elected to adopt this guidance retrospectively. Further, the Company has elected to account for forfeitures as they occur, which resulted in an immaterial cumulative-effect adjustment to retained earnings. Recently Issued Accounting Pronouncements In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (“ASU 2016-15”), which is intended to reduce diversity in practice in how certain transactions are classified in the statement of cash flows. The guidance addresses eight specific cash flow issues for which current GAAP is either unclear or does not include specific guidance. ASU 2016-15 is effective for interim and annual periods beginning after December 15, 2017, with early adoption permitted, provided that it is adopted in its entirety in the same period. Currently, the Company does not expect the impact of adopting ASU 2016-15 to have a material effect on its consolidated statements of cash flows. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), which significantly changes accounting for leases by requiring that lessees recognize a right-of-use asset and a related lease liability representing the obligation to make lease payments, for virtually all lease transactions. Additional disclosures about an entity’s lease transactions will also be required. ASU 2016-02 defines a lease as “a contract, or part of a contract, that conveys the right to control the use of identified property, plant or equipment (an identified asset) for a period of time in exchange for consideration.” ASU 2016-02 is effective for interim and annual periods beginning after December 15, 2018 with early adoption permitted. ASU 2016-02 requires companies to recognize and measure leases at the beginning of the earliest period presented in the financial statements using a modified retrospective approach. Although the Company is in the process of evaluating ASU 2016-02 and the impact the adoption of the new standard will have on its consolidated financial statements and related disclosures, it is currently anticipated to result in an increase in the assets and liabilities recorded on its consolidated balance sheets. The Company will evaluate its existing contracts including, but not limited to, drilling rig contracts and gathering, processing, and transportation contracts to determine if they qualify for lease accounting under ASU 2016-02. In May 2014, the FASB issued ASU No. 2014-09, Revenue From Contracts With Customers (Topic 606) (“ASU 2014-09”), which will require entities to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 will supersede most current guidance related to revenue recognition when it becomes effective. The new standard also will require expanded disclosures regarding the nature, timing, amount and certainty of revenue and cash flows from contracts with customers. ASU 2014-09 is effective for interim and annual periods beginning after December 15, 2017 with early adoption permitted for interim and annual periods beginning after December 31, 2016. Companies are permitted to adopt ASU 2014-09 through the use of either the full retrospective approach, meaning the standard is applied to all of the periods presented, or a modified retrospective approach, meaning the cumulative effect of initially applying the standard is recognized in the most current period presented in the financial statements. The Company is in the process of assessing the impact of ASU 2014-09 with the assistance of an outside consultant. The assessment consists of analyzing the Company’s existing contracts and current accounting policies and practices to identify potential differences that would result from applying the requirements of ASU 2014-09. Once the assessment is complete, the Company will implement appropriate changes to its business processes, systems or controls to support recognition and disclosure pursuant to ASU 2014-09. Based on assessments performed to date, the Company currently does not expect the impact of adopting ASU 2014-09 to have a material effect on the timing or method of revenue recognition as the performance obligations are not materially changed under ASU 2014-09. The Company currently plans to apply the modified retrospective method upon adoption and plans to adopt the guidance on the effective date of January 1, 2018, however, the Company continues to review the impact of ASU 2014-09 on its consolidated financial statements and related disclosures. Net Income (Loss) Per Common Share Supplemental net income (loss) per common share information is provided below: Three Months Ended 2017 2016 (In thousands, except per share amounts) Net Income (Loss) $40,021 ($311,395 ) Basic weighted average common shares outstanding 65,188 58,360 Effect of dilutive instruments 590 — Diluted weighted average common shares outstanding 65,778 58,360 Net Income (Loss) Per Common Share Basic $0.61 ($5.34 ) Diluted $0.61 ($5.34 ) The table below presents the dilutive and anti-dilutive weighted average common shares outstanding for the three months ended March 31, 2017 and 2016 : Three Months Ended 2017 2016 (In thousands) Dilutive 590 — Anti-dilutive (1) 5 665 (1) For the three months ended March 31, 2016 , the Company reported a net loss. As a result, all potentially dilutive common shares outstanding were anti-dilutive.

Acquisitions

Acquisitions	3 Months Ended
	Mar. 31, 2017
Acquisitions [Abstract]
Acquisitions Disclosures	3. Acquisition Sanchez Acquisition On December 14, 2016, the Company completed its initial closing of the acquisition of oil and gas properties in the Eagle Ford Shale from Sanchez Energy Corporation and SN Cotulla Assets, LLC, a subsidiary of Sanchez Energy Corporation (the “Sanchez Acquisition”). The Sanchez Acquisition was accounted for under the acquisition method of accounting whereby the purchase price was allocated to the assets acquired and liabilities assumed based on their estimated acquisition date fair values based on then available information. At the time of the initial close, an adjustment to the purchase price of $16.8 million was made for leases that were not conveyed to the Company. On January 9, 2017, the Company paid $7.0 million of the $16.8 million for certain of the outstanding leases which were conveyed to the Company. See the updated purchase price allocation presented below. The purchase price allocation for the Sanchez Acquisition is preliminary and subject to change based on closings subsequent to March 31, 2017, related to the remaining leases that were not conveyed to the Company at the initial closing on December 14, 2016 or the subsequent closing on January 9, 2017 and final updates to purchase price adjustments primarily relate to net cash flows from the acquired wells from the effective date to the closing date. The following presents the purchase price and the preliminary allocation of the purchase price to the assets acquired and liabilities assumed as of the acquisition date. The Company currently expects these amounts will be finalized during the fourth quarter of 2017. Preliminary Purchase Price Allocation (In thousands) Assets Other current assets $477 Oil and gas properties Proved properties 94,664 Unproved properties 70,309 Total oil and gas properties 164,973 Total assets acquired $165,450 Liabilities Revenues and royalties payable $1,442 Other current liabilities 323 Asset retirement obligations 2,054 Other liabilities 1,078 Total liabilities assumed $4,897 Net Assets Acquired $160,553 On April 13, 2017, the final payment of $9.8 million was made for the leases that were not conveyed to the Company at the initial closing or the subsequent closing on January 9, 2017. This amount has not been reflected in the preliminary purchase price allocation presented above.

Property And Equipment, Net

Property And Equipment, Net	3 Months Ended
	Mar. 31, 2017
Property, Plant and Equipment [Abstract]
Property And Equipment, Net	4. Property and Equipment, Net As of March 31, 2017 and December 31, 2016 , total property and equipment, net consisted of the following: March 31, December 31, (In thousands) Oil and gas properties, full cost method Proved properties $4,817,044 $4,687,416 Accumulated depreciation, depletion and amortization and impairments (3,445,709 ) (3,392,749 ) Proved properties, net 1,371,335 1,294,667 Unproved properties, not being amortized Unevaluated leasehold and seismic costs 221,039 211,067 Capitalized interest 32,231 29,894 Total unproved properties, not being amortized 253,270 240,961 Other property and equipment 23,240 23,127 Accumulated depreciation (13,641 ) (12,995 ) Other property and equipment, net 9,599 10,132 Total property and equipment, net $1,634,204 $1,545,760 Average depreciation, depletion and amortization (“DD&A”) per Boe of proved properties was $12.69 and $15.22 for the three months ended March 31, 2017 and 2016 , respectively. The Company capitalized internal costs of employee compensation and benefits, including stock-based compensation, directly associated with acquisition, exploration and development activities totaling $5.4 million and $4.4 million for the three months ended March 31, 2017 and 2016 , respectively. Unproved properties, not being amortized, include unevaluated leasehold and seismic costs associated with specific unevaluated properties and related capitalized interest. The Company capitalized interest costs associated with its unproved properties totaling $3.8 million and $5.6 million for the three months ended March 31, 2017 and 2016 , respectively. Divestiture During the first quarter of 2017, the Company sold a small acreage position in the Delaware Basin for net proceeds of $15.3 million . The proceeds from this sale were recognized as a reduction of proved oil and gas properties. Impairment of Proved Oil and Gas Properties At the end of each quarter, the net book value of oil and gas properties, less related deferred income taxes, are limited to the “cost center ceiling” equal to (i) the sum of (a) the present value of estimated future net revenues from proved oil and gas reserves, less estimated future expenditures to be incurred in developing and producing the proved reserves computed using a discount factor of 10% , (b) the costs of unproved properties not being amortized, and (c) the lower of cost or estimated fair value of unproved properties included in the costs being amortized; less (ii) related income tax effects. Any excess of the net book value of oil and gas properties, less related deferred income taxes, over the cost center ceiling is recognized as an impairment of proved oil and gas properties. An impairment recognized in one period may not be reversed in a subsequent period even if higher commodity prices in the future result in a cost center ceiling in excess of the net book value of oil and gas properties, less related deferred income taxes. The estimated future net revenues used in the cost center ceiling are calculated using the average realized prices for sales of crude oil, NGLs, and natural gas on the first calendar day of each month during the 12-month period prior to the end of the current period (“12-Month Average Realized Price”), held flat for the life of the production, except where different prices are fixed and determinable from applicable contracts for the remaining term of those contracts. Prices do not include the impact of derivative instruments as the Company elected not to meet the criteria to qualify derivative instruments for hedge accounting treatment. The Company did not recognize an impairment of proved oil and gas properties for the three months ended March 31, 2017. Primarily due to declines in the 12-Month Average Realized Price of crude oil from December 31, 2015 to March 31, 2016, the Company recognized an impairment of proved oil and gas properties for the three months ended March 31, 2016 . Details of the 12-Month Average Realized Price of crude oil for the three months ended March 31, 2017 and 2016 and the impairment of proved oil and gas properties for the three months ended March 31, 2016 are summarized in the table below: Three Months Ended 2017 2016 Impairment of proved oil and gas properties (in thousands) $— $274,413 Crude Oil 12-Month Average Realized Price ($/Bbl) - Beginning of period $39.60 $47.24 Crude Oil 12-Month Average Realized Price ($/Bbl) - End of period $44.98 $43.13 Percentage increase (decrease) 14 % (9 %)

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	5. Income Taxes The Company’s estimated annual effective income tax rates are used to allocate expected annual income tax expense or benefit to interim periods. The rates are the ratio of estimated annual income tax expense or benefit to estimated annual income or loss before income taxes by taxing jurisdiction, except for discrete items, which are significant, unusual or infrequent items for which income taxes are computed and recorded in the interim period in which the discrete item occurs. The estimated annual effective income tax rates are applied to the year-to-date income or loss before income taxes by taxing jurisdiction to determine the income tax expense or benefit allocated to the interim period. The Company updates its estimated annual effective income tax rates on a quarterly basis considering the geographic mix of income or loss attributable to the tax jurisdictions in which the Company operates. The Company’s income tax (expense) benefit differs from the income tax (expense) benefit computed by applying the U.S. federal statutory corporate income tax rate of 35% to income (loss) before income taxes as follows: Three Months Ended 2017 2016 (In thousands) Income (loss) before income taxes $40,021 ($311,274 ) Income tax (expense) benefit at the statutory rate (14,007 ) 108,946 State income tax (expense) benefit, net of U.S. federal income taxes (710 ) 1,619 Tax shortfalls from stock-based compensation expense (2,592 ) — Deferred tax assets valuation allowance 17,369 (110,679 ) Other (60 ) (7 ) Income tax expense $— ($121 ) Deferred Tax Assets Valuation Allowance Deferred tax assets are recorded for net operating losses and temporary differences between the book and tax basis of assets and liabilities expected to produce tax deductions in future periods. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those deferred tax assets would be deductible. The Company assesses the realizability of its deferred tax assets on a quarterly basis by considering whether it is more likely than not that all or a portion of the deferred tax assets will not be realized. The Company considers all available evidence (both positive and negative) when determining whether a valuation allowance is required. In making this assessment, the Company evaluated possible sources of taxable income that may be available to realize the deferred tax assets, including projected future taxable income, the reversal of existing temporary differences, taxable income in carryback years and available tax planning strategies. A significant item of objective negative evidence considered was the cumulative historical three year pre-tax loss and a net deferred tax asset position at March 31, 2017 , driven primarily by the impairments of proved oil and gas properties recognized beginning in the third quarter of 2015 and continuing through the third quarter of 2016, which limits the ability to consider other subjective evidence such as the Company’s potential for future growth. Beginning in the third quarter of 2015, and continuing through the first quarter of 2017, the Company concluded that it was more likely than not the deferred tax assets will not be realized. As a result, the net deferred tax assets at the end of each quarter, including March 31, 2017 , were reduced to zero . As a result of adopting ASU 2016-09, the Company recognized previously unrecognized windfall tax benefits which resulted in a cumulative-effect adjustment to retained earnings of approximately $15.7 million . This adjustment increased deferred tax assets, which in turn increased the valuation allowance by the same amount as of the beginning of 2017, resulting in a net cumulative-effect adjustment to retained earnings of zero and brought the valuation allowance to $580.1 million as of January 1, 2017. For the three months ended March 31, 2017, as a result of current quarter activity and the recognition of tax shortfalls from stock-based compensation expense that are now recognized in income tax expense due to the adoption of ASU 2016-09, a partial release of $17.4 million from the valuation allowance was needed to bring the net deferred tax assets to zero. After the impact of the adoption of ASU 2016-09 and the current quarter activity, the valuation allowance as of March 31, 2017 was $562.7 million . The Company will continue to evaluate whether the valuation allowance is needed in future reporting periods. The valuation allowance will remain until the Company can conclude that the net deferred tax assets are more likely than not to be realized. Future events or new evidence which may lead the Company to conclude that it is more likely than not its net deferred tax assets will be realized include, but are not limited to, cumulative historical pre-tax earnings, improvements in crude oil prices, and taxable events that could result from one or more transactions. The valuation allowance does not preclude the Company from utilizing the tax attributes if the Company recognizes taxable income. As long as the Company continues to conclude that the valuation allowance against its net deferred tax assets is necessary, the Company will have no significant deferred income tax expense or benefit.

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Debt	6. Long-Term Debt Long-term debt consisted of the following as of March 31, 2017 and December 31, 2016 : March 31, December 31, (In thousands) Senior Secured Revolving Credit Facility due 2018 $123,000 $87,000 7.50% Senior Notes due 2020 600,000 600,000 Unamortized premium for 7.50% Senior Notes 960 1,020 Unamortized debt issuance costs for 7.50% Senior Notes (7,189 ) (7,573 ) 6.25% Senior Notes due 2023 650,000 650,000 Unamortized debt issuance costs for 6.25% Senior Notes (9,150 ) (9,454 ) Other long-term debt due 2028 4,425 4,425 Long-term debt $1,362,046 $1,325,418 Senior Secured Revolving Credit Facility The Company has a senior secured revolving credit facility with a syndicate of banks that, as of March 31, 2017 , had a borrowing base of $600.0 million , with $123.0 million of borrowings outstanding at a weighted average interest rate of 2.95% . As of March 31, 2017 , the Company also had $0.4 million in letters of credit outstanding, which reduce the amounts available under the revolving credit facility. As of March 31, 2017, the credit agreement governing the revolving credit facility provided for interest-only payments until July 2, 2018, when the credit agreement was scheduled to mature and any outstanding borrowings would become due. The borrowing base under the credit agreement is subject to regular redeterminations in the spring and fall of each year, as well as special redeterminations described in the credit agreement, which in each case may reduce the amount of the borrowing base. The amount the Company is able to borrow with respect to the borrowing base is subject to compliance with the financial covenants and other provisions of the credit agreement. The capitalized terms which are not defined in this description of the revolving credit facility, shall have the meaning given to such terms in the credit agreement. The obligations of the Company under the credit agreement are guaranteed by the Company’s material domestic subsidiaries and are secured by liens on substantially all of the Company’s assets, including a mortgage lien on oil and gas properties having at least 90% of the total value of the oil and gas properties included in the Company’s reserve report used in its most recent redetermination. Borrowings outstanding under the credit agreement bear interest at the Company’s option at either (i) a base rate for a base rate loan plus the margin set forth in the table below, where the base rate is defined as the greatest of the prime rate, the federal funds rate plus 0.50% and the adjusted LIBO rate plus 1.00% , or (ii) an adjusted LIBO rate for a Eurodollar loan plus the margin set forth in the table below. The Company also incurs commitment fees at rates, as of March 31, 2017, as set forth in the table below on the unused portion of lender commitments, which are included in interest expense, net in the consolidated statements of operations. Ratio of Outstanding Borrowings and Letters of Credit to Lender Commitments Applicable Margin for Base Rate Loans Applicable Margin for Eurodollar Loans Commitment Fee Less than 25% 1.00% 2.00% 0.500% Greater than or equal to 25% but less than 50% 1.25% 2.25% 0.500% Greater than or equal to 50% but less than 75% 1.50% 2.50% 0.500% Greater than or equal to 75% but less than 90% 1.75% 2.75% 0.500% Greater than or equal to 90% 2.00% 3.00% 0.500% As of March 31, 2017, the Company was subject to certain covenants under the terms of the credit agreement, which include the maintenance of the following financial covenants determined as of the last day of each quarter: (1) a ratio of Total Secured Debt to EBITDA of not more than 2.00 to 1.00, (2) a Current Ratio of not less than 1.00 to 1.00, and (3) a ratio of EBITDA to Interest Expense of not less than 2.50 to 1.00. As defined in the credit agreement, EBITDA includes the last four quarters after giving pro forma effect to EBITDA for material acquisitions and dispositions of oil and gas properties, Interest Expense is comprised of the aggregate interest expense paid in cash for the last four quarters, and the Current Ratio includes an add back of the unused portion of lender commitments. As of March 31, 2017 , the ratio of Total Secured Debt to EBITDA was 0.30 to 1.00, the Current Ratio was 2.56 to 1.00 and the ratio of EBITDA to Interest Expense was 4.53 to 1.00. Because the financial covenants are determined as of the last day of each quarter, the ratios can fluctuate significantly period to period as the level of borrowings outstanding under the credit agreement are impacted by the timing of cash flows from operations, capital expenditures, acquisitions and dispositions of oil and gas properties and securities offerings. The credit agreement also places restrictions on the Company and certain of its subsidiaries with respect to additional indebtedness, liens, dividends and other payments to shareholders, repurchases or redemptions of the Company’s common stock, redemptions of senior notes, investments, acquisitions, mergers, asset dispositions, transactions with affiliates, hedging transactions and other matters. The credit agreement is subject to customary events of default, including in connection with a change in control. If an event of default occurs and is continuing, the lenders may elect to accelerate amounts due under the credit agreement (except in the case of a bankruptcy event of default, in which case such amounts will automatically become due and payable). On May 4, 2017, the Company entered into a ninth amendment to its credit agreement governing the revolving credit facility. See “Note 13. Subsequent Events” for further details.

Commitments And Contingencies

Commitments And Contingencies	3 Months Ended
	Mar. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	7. Commitments and Contingencies From time to time, the Company is party to certain legal actions and claims arising in the ordinary course of business. While the outcome of these events cannot be predicted with certainty, management does not currently expect these matters to have a materially adverse effect on the financial position or results of operations of the Company. The results of operations and financial position of the Company continue to be affected from time to time in varying degrees by domestic and foreign political developments as well as legislation and regulations pertaining to restrictions on oil and gas production, imports and exports, natural gas regulation, tax increases, environmental regulations and cancellation of contract rights. Both the likelihood and overall effect of such occurrences on the Company vary greatly and are not predictable.

Shareholders' Equity and Stock

Shareholders' Equity and Stock Incentive Plans	3 Months Ended
	Mar. 31, 2017
Shareholders' Equity and Stock Incentive Plans [Abstract]
Shareholders' Equity and Share-based Payments	8. Shareholders’ Equity and Stock-Based Compensation Plans As of March 31, 2017 , there were 26,275 common shares remaining available for grant under the Incentive Plan of Carrizo Oil & Gas, Inc., as amended (the “Incentive Plan”). The issuance of a restricted stock award, restricted stock unit, or performance share counts as 1.35 shares against the number of common shares available for grant under the Incentive Plan. Stock-based compensation expense associated with restricted stock awards and units, stock appreciation rights to be settled in cash (“SARs”) and performance shares is reflected as general and administrative expense in the consolidated statements of operations, net of amounts capitalized to oil and gas properties. Restricted Stock Awards and Units. Under the Incentive Plan, restricted stock awards can be granted to employees and independent contractors and restricted stock units can be granted to employees, independent contractors, and non-employee directors. As of March 31, 2017 , unrecognized compensation costs related to unvested restricted stock awards and units was $31.4 million and will be recognized over a weighted average period of 2.4 years. The table below summarizes restricted stock award and unit activity for the first quarter of 2017: Restricted Stock Awards and Units Weighted Average Grant Date Fair Value For the Three Months Ended March 31, 2017 Unvested restricted stock awards and units, beginning of period 1,111,710 $36.93 Granted 749,396 $27.07 Vested (569,145 ) $39.48 Forfeited (3,933 ) $29.42 Unvested restricted stock awards and units, end of period 1,288,028 $30.09 During the first quarter of 2017, the Company granted 695,658 restricted stock units to employees and independent contractors with a grant date fair value of $18.8 million as part of its annual grant of long-term equity incentive awards. These restricted stock units will vest ratably over a three -year period. All of these restricted stock units contain a service condition, and certain of these restricted stock units also contain a performance condition. The performance condition has not yet been met. In addition, the Company granted 44,465 restricted stock units to certain employees and independent contractors with a grant date fair value of $1.2 million in lieu of a portion of their annual incentive bonus otherwise payable to them in cash under the Company’s performance-based annual incentive bonus program. These restricted stock units vested substantially concurrent with the time of grant. Stock Appreciation Rights. SARs can be granted to employees and independent contractors under the Incentive Plan or the Carrizo Oil & Gas, Inc. Cash-Settled Stock Appreciation Rights Plan (“Cash SAR Plan”). SARs granted under the Incentive Plan can be settled in shares of common stock or cash, at the option of the Company, while SARs granted under the Cash SAR Plan may only be settled in cash. As of March 31, 2017 , all outstanding SARs will be settled solely in cash. The liability for SARs as of March 31, 2017 was $6.4 million , of which $6.3 million was classified as “Other current liabilities,” with the remaining $0.1 million classified as “Other liabilities” in the consolidated balance sheets. As of December 31, 2016 , the liability for SARs was $11.5 million , of which $10.0 million was classified as “Other current liabilities,” with the remaining $1.5 million classified as “Other liabilities” in the consolidated balance sheets. Unrecognized compensation costs related to unvested SARs was $5.9 million as of March 31, 2017 , and will be recognized over a weighted average period of 1.8 years. The table below summarizes the activity for SARs for the first quarter of 2017: Stock Appreciation Rights Weighted Average Exercise Prices Weighted Average Remaining Life (In years) Aggregate Intrinsic Value (In millions) Aggregate Intrinsic Value of Exercises (In millions) For the Three Months Ended March 31, 2017 Outstanding, beginning of period 722,638 $23.69 Granted 342,440 $26.94 Exercised (100,000 ) $17.28 $1.3 Forfeited — — Outstanding, end of period 965,078 $25.51 3.4 $2.5 Exercisable, end of period 436,739 $23.62 1.8 $2.0 During the first quarter of 2017, the Company granted 342,440 SARs under the Cash SAR Plan with a grant date fair value of $4.1 million to certain employees and independent contractors as part of its annual grant of long-term equity incentive awards. The grant date fair value of the SARs was calculated using the Black-Scholes-Merton option pricing model. These SARs will vest ratably over a two -year period and expire five years from the grant date. All of these SARs contain a service condition and performance condition. The performance condition has not yet been met. The following table summarizes the assumptions used to calculate the grant date fair value of SARs granted during the first quarter of 2017 : Grant Date Fair Value Assumptions Expected term (in years) 4.24 Expected volatility 54.3 % Risk-free interest rate 1.8 % Dividend yield — % Grant date fair value $12.00 Performance Shares. Under the Incentive Plan, the Company can grant performance shares to employees and independent contractors, where each performance share represents the right to receive one share of common stock. The number of performance shares that will vest is based on the ranges from zero to 200% of the target performance shares granted based on the total shareholder return (“TSR”) of the Company’s common stock relative to the TSR achieved by a specified industry peer group over an approximate three year performance period, the last day of which is also the vesting date. As of March 31, 2017 , unrecognized compensation costs related to unvested performance shares was $3.8 million and will be recognized over a weighted average period of 2.1 years. The table below summarizes performance share activity for the first quarter of 2017 : Performance Shares Weighted Average Grant Date Fair Value For the Three Months Ended March 31, 2017 Unvested performance shares, beginning of period 154,510 $58.44 Granted 46,787 $35.14 Vested (1) (56,342 ) $68.15 Forfeited — — Unvested performance shares, end of period 144,955 $47.14 (1) The vested performance shares presented in the table above are the target performance shares that were granted in 2014. The Company ’ s final TSR ranking relative to the specified industry peer group resulted in the vesting of 164% of the target performance shares granted, or an additional 35,858 shares. During the first quarter of 2017, the Company granted 46,787 target performance shares to certain employees and independent contractors with a grant date fair value of $1.6 million as part of its annual grant of long-term equity incentive awards. The grant date fair value of the performance awards was calculated using a Monte Carlo simulation. In addition to the market condition described above, the performance shares also contain a service condition and performance condition. The performance condition has not yet been met. The following table summarizes the assumptions used to calculate the grant date fair value of the performance shares granted during the first quarter of 2017 : Grant Date Fair Value Assumptions Number of simulations 500,000 Expected term (in years) 2.98 Expected volatility 59.2 % Risk-free interest rate 1.5 % Dividend yield — % Grant date fair value $35.14 Stock-Based Compensation Expense, Net The Company recognized the following stock-based compensation expense, net for the periods indicated: Three Months Ended 2017 2016 (In thousands) Restricted stock awards and units $5,849 $11,594 Stock appreciation rights (3,686 ) 1,232 Performance shares 706 616 2,869 13,442 Less: amounts capitalized to oil and gas properties (855 ) (1,920 ) Total stock-based compensation expense, net $2,014 $11,522

Derivative Instruments

Derivative Instruments	3 Months Ended
	Mar. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	9. Derivative Instruments The Company uses commodity derivative instruments to reduce its exposure to commodity price volatility for a portion of its forecasted crude oil and natural gas production and thereby achieve a more predictable level of cash flows to support the Company’s drilling and completion capital expenditure program. The Company does not enter into derivative instruments for speculative or trading purposes. The Company’s commodity derivative instruments consist of fixed price swaps, three-way collars and purchased and sold call options, which are described below. Fixed Price Swaps: The Company receives a fixed price and pays a variable market price to the counterparties over specified periods for contracted volumes. Three-Way Collars: A three-way collar is a combination of options including a purchased put option (fixed floor price), a sold call option (fixed ceiling price) and a sold put option (fixed sub-floor price). These contracts offer a higher fixed ceiling price relative to a costless collar but limit the Company’s protection from decreases in commodity prices below the fixed floor price. At settlement, if the market price is between the fixed floor price and the fixed sub-floor price or is above the fixed ceiling price, the Company receives the fixed floor price or pays the market price, respectively. If the market price is below the fixed sub-floor price, the Company receives the market price plus the difference between the fixed floor price and the fixed sub-floor price. If the market price is between the fixed floor price and fixed ceiling price, no payments are due from either party. Sold Call Options : These contracts give the counterparties the right, but not the obligation, to buy contracted volumes from the Company over specified periods and prices in the future. At settlement, if the market price exceeds the fixed price of the call option, the Company pays the counterparty the excess. If the market price settles below the fixed price of the call option, no payment is due from either party. These contracts require the counterparties to pay premiums to the Company that represent the fair value of the call option as of the date of purchase. Purchased Call Options : These contracts give the Company the right, but not the obligation, to buy contracted volumes from the counterparties over specified periods and prices in the future. At settlement, if the market price exceeds the fixed price of the call option, the counterparties pay the Company the excess. If the market price settles below the fixed price of the call option, no payment is due from either party. These contracts require the Company to pay premiums to the counterparties that represent the fair value of the call option as of the date of purchase. All of the Company’s purchased call options were executed contemporaneously with sales of call options to increase the fixed price of existing sold call options and therefore are presented on a net basis in the summary of open crude oil derivative positions below. Premiums : In lieu of receiving payments for premiums from its counterparties of sold call options, the Company has used the associated premium value to obtain higher fixed prices on fixed price swaps which were executed contemporaneously with those sold call options. The Company elected to defer payment of premiums associated with its purchased call options until the applicable contracts settle on a monthly basis. As of March 31, 2017, the Company had premium obligations of approximately $4.2 million , of which $2.0 million is classified as current derivative liabilities and $2.2 million is classified as noncurrent derivative liabilities on the Company’s consolidated balance sheets. As of December 31, 2016, the Company had premium obligations of approximately $4.6 million , of which $2.0 million was classified as current derivative liabilities and $2.6 million was classified as noncurrent derivative liabilities on the Company’s consolidated balance sheets. The following sets forth a summary of the Company’s crude oil derivative positions at average NYMEX prices as of March 31, 2017 : Period Type of Contract Crude Oil Volumes (in Bbls/d) Weighted Average Floor Price ($/Bbl) Weighted Average Ceiling Price ($/Bbl) Q2 2017 Fixed Price Swaps 12,000 $50.13 Q3 2017 Fixed Price Swaps 6,000 $54.15 Q4 2017 Fixed Price Swaps 3,000 $55.01 FY 2018 Sold Call Options 2,488 $60.00 FY 2018 Net Sold Call Options 900 $75.00 FY 2019 Sold Call Options 2,975 $62.50 FY 2019 Net Sold Call Options 900 $77.50 FY 2020 Sold Call Options 3,675 $65.00 FY 2020 Net Sold Call Options 900 $80.00 The following sets forth a summary of the Company’s natural gas derivative positions at average NYMEX prices as of March 31, 2017 : Period Type of Contract Natural Gas Volumes Weighted Average Floor Price ($/MMBtu) Weighted Q2 - Q4 2017 Fixed Price Swaps 20,000 $3.30 Q2 - Q4 2017 Sold Call Options 33,000 $3.00 FY 2018 Sold Call Options 33,000 $3.25 FY 2019 Sold Call Options 33,000 $3.25 FY 2020 Sold Call Options 33,000 $3.50 See “Note 13. Subsequent Events” for details of derivative positions entered into subsequent to March 31, 2017 . The Company typically has numerous hedge positions that span several time periods and often result in both fair value asset and liability positions held with that counterparty, which positions are all offset to a single fair value asset or liability at the end of each reporting period, including the deferred premiums associated with its hedge positions. The Company nets its derivative instrument fair values executed with the same counterparty along with deferred premiums pursuant to ISDA master agreements, which provide for net settlement over the term of the contract and in the event of default or termination of the contract. Counterparties to the Company’s derivative instruments who are also lenders under the Company’s credit agreement allow the Company to satisfy any need for margin obligations associated with derivative instruments where the Company is in a net liability position with its counterparties with the collateral securing the credit agreement, thus eliminating the need for independent collateral posting. Counterparties who are not lenders under the Company’s credit agreement can require derivative contracts to be novated to a lender if the net liability position exceeds our unsecured credit limit with that counterparty and therefore do not require the posting of cash collateral. Because the counterparties have investment grade credit ratings, or the Company has obtained guarantees from the applicable counterparty’s investment grade parent company, the Company believes it does not have significant credit risk and accordingly does not currently require its counterparties to post collateral to support the net asset positions of its derivative instruments. Although the Company does not currently anticipate nonperformance from its counterparties, it continually monitors the credit ratings of its counterparties or its counterparty’s parent company. Derivative Assets and Liabilities All derivative instruments are recorded on the Company’s consolidated balance sheets as either an asset or liability measured at fair value. The combined derivative instrument fair value assets and liabilities recorded in the Company’s consolidated balance sheets as of March 31, 2017 and December 31, 2016 are summarized below: March 31, 2017 Gross Amounts Recognized Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts Presented in the Consolidated Balance Sheets (In thousands) Derivative assets Derivative assets-current $2,417 ($1,381 ) $1,036 Derivative assets-non current 106 (106 ) — Derivative liabilities Derivative liabilities-current (8,837 ) 1,381 (7,456 ) Derivative liabilities-non current (18,781 ) 106 (18,675 ) Total ($25,095 ) $— ($25,095 ) December 31, 2016 Gross Amounts Recognized Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts Presented in the Consolidated Balance Sheets (In thousands) Derivative assets Derivative assets-current $6,507 ($5,270 ) $1,237 Derivative assets-non current 1,313 (1,313 ) — Derivative liabilities Derivative liabilities-current (27,871 ) 5,270 (22,601 ) Derivative liabilities-non current (28,841 ) 1,313 (27,528 ) Total ($48,892 ) $— ($48,892 ) See “Note 10. Fair Value Measurements” for additional details regarding the fair value of the Company’s derivative positions. (Gain) Loss on Derivatives, Net The Company has elected not to meet the criteria to qualify its derivative instruments for hedge accounting treatment. Therefore, all gains and losses as a result of changes in the fair value of derivative instruments are recognized as (gain) loss on derivatives, net in the Company’s consolidated statements of operations in the period in which the changes occur. The effect of derivative instruments on the Company’s consolidated statements of operations for the three months ended March 31, 2017 and 2016 by commodity is summarized below: Three Months Ended 2017 2016 (In thousands) (Gain) Loss on Derivatives, Net Crude oil ($18,480 ) ($21,891 ) Natural gas (6,836 ) 11,338 Total (Gain) Loss on Derivatives, Net ($25,316 ) ($10,553 ) The cash flow impacts of the Company’s derivative instruments are presented as separate line items within the net cash provided by operating activities in the Company’s consolidated statements of cash flows.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	10. Fair Value Measurements Accounting guidelines for measuring fair value establish a three-level valuation hierarchy for disclosure of fair value measurements. The valuation hierarchy categorizes assets and liabilities measured at fair value into one of three different levels depending on the observability of the inputs employed in the measurement. The three levels are defined as follows: Level 1 – Observable inputs such as quoted prices in active markets at the measurement date for identical, unrestricted assets or liabilities. Level 2 – Other inputs that are observable directly or indirectly such as quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability. Level 3 – Unobservable inputs for which there is little or no market data and which the Company makes its own assumptions about how market participants would price the assets and liabilities. Assets and Liabilities Measured at Fair Value on a Recurring Basis The following tables summarize the Company’s assets and liabilities measured at fair value on a recurring basis as of March 31, 2017 and December 31, 2016 : March 31, 2017 Level 1 Level 2 Level 3 (In thousands) Derivative assets $— $1,036 $— Derivative liabilities $— ($21,970 ) $— December 31, 2016 Level 1 Level 2 Level 3 (In thousands) Derivative assets $— $1,237 $— Derivative liabilities $— ($45,552 ) $— The Company uses Level 2 inputs to measure the fair value of the Company’s commodity derivative instruments based on a third-party industry-standard pricing model using contract terms and prices and assumptions and inputs that are substantially observable in active markets throughout the full term of the instruments including forward oil and gas price curves, discount rates and volatility factors. The fair values are also compared to the values provided by the counterparties for reasonableness and are adjusted for the counterparties’ credit quality for derivative assets and the Company’s credit quality for derivative liabilities. The derivative asset and liability fair values reported in the consolidated balance sheets are as of the balance sheet date and subsequently change as a result of changes in commodity prices, market conditions and other factors. The Company typically has numerous hedge positions that span several time periods and often result in both derivative assets and liabilities with the same counterparty, which positions are all offset to a single derivative asset or liability in the consolidated balance sheets, including the deferred premiums associated with its hedge positions. The Company nets the fair values of its derivative assets and liabilities associated with derivative instruments executed with the same counterparty, along with deferred premiums, pursuant to ISDA master agreements, which provide for net settlement over the term of the contract and in the event of default or termination of the contract. The Company had no transfers into Level 1 and no transfers into or out of Level 2 for the three months ended March 31, 2017 and 2016 . Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis The fair value measurements of assets acquired and liabilities assumed are measured on a nonrecurring basis on the acquisition date using a discounted cash flow model based on inputs that are not observable in the market and therefore represent Level 3 inputs. Significant inputs to the valuation of acquired oil and gas properties include estimates of estimated volumes of oil and gas reserves, production rates, future commodity prices, timing of development, future operating and development costs and a risk adjusted discount rate. The fair value measurements of asset retirement obligations are measured on a nonrecurring basis when a well is drilled or acquired or when production equipment and facilities are installed or acquired using a discounted cash flow model based on inputs that are not observable in the market and therefore represent Level 3 inputs. Significant inputs to the fair value measurement of asset retirement obligations include estimates of the costs of plugging and abandoning oil and gas wells, removing production equipment and facilities and restoring the surface of the land as well as estimates of the economic lives of the oil and gas wells and future inflation rates. Fair Value of Other Financial Instruments The Company’s other financial instruments consist of cash and cash equivalents, receivables, payables, and long-term debt, which are classified as Level 1 under the fair value hierarchy. The carrying amounts of cash and cash equivalents, receivables, and payables approximate fair value due to the highly liquid or short-term nature of these instruments. The carrying amount of long-term debt associated with borrowings outstanding under the Company’s revolving credit facility approximates fair value as borrowings bear interest at variable rates. The following table presents the carrying amounts of the Company’s senior notes and other long-term debt, net of debt premiums and debt issuance costs, with the fair values measured using Level 1 inputs based on quoted secondary market trading prices. March 31, 2017 December 31, 2016 Carrying Amount Fair Value Carrying Amount Fair Value (In thousands) 7.50% Senior Notes due 2020 $593,771 $616,500 $593,447 $624,750 6.25% Senior Notes due 2023 640,850 650,000 640,546 672,750 Other long-term debt due 2028 4,425 4,425 4,425 4,419

Condensed Consolidating Financi

Condensed Consolidating Financial Information	3 Months Ended
	Mar. 31, 2017
Condensed Consolidating Financial Information [Abstract]
Condensed Consolidating Financial Information	11. Condensed Consolidating Financial Information The rules of the SEC require that condensed consolidating financial information be provided for a subsidiary that has guaranteed the debt of a registrant issued in a public offering, where the guarantee is full, unconditional and joint and several and where the voting interest of the subsidiary is 100% owned by the registrant. The Company is, therefore, presenting condensed consolidating financial information on a parent company, combined guarantor subsidiaries, combined non-guarantor subsidiaries and consolidated basis and should be read in conjunction with the consolidated financial statements. The financial information may not necessarily be indicative of results of operations, cash flows, or financial position had such guarantor subsidiaries operated as independent entities. CARRIZO OIL & GAS, INC. CONDENSED CONSOLIDATING BALANCE SHEETS (In thousands) (Unaudited) March 31, 2017 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Assets Total current assets $2,724,856 $66,199 $— ($2,717,829 ) $73,226 Total property and equipment, net 41,196 1,593,134 3,800 (3,926 ) 1,634,204 Investment in subsidiaries (1,223,475 ) — — 1,223,475 — Other assets 6,855 155 — — 7,010 Total Assets $1,549,432 $1,659,488 $3,800 ($1,498,280 ) $1,714,440 Liabilities and Shareholders’ Equity Current liabilities $90,083 $2,854,994 $3,800 ($2,720,849 ) $228,028 Long-term liabilities 1,372,638 27,969 — 15,878 1,416,485 Total shareholders’ equity 86,711 (1,223,475 ) — 1,206,691 69,927 Total Liabilities and Shareholders’ Equity $1,549,432 $1,659,488 $3,800 ($1,498,280 ) $1,714,440 December 31, 2016 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Assets Total current assets $2,735,830 $63,513 $— ($2,726,355 ) $72,988 Total property and equipment, net 42,181 1,503,695 3,800 (3,916 ) 1,545,760 Investment in subsidiaries (1,282,292 ) — — 1,282,292 — Other assets 7,423 156 — — 7,579 Total Assets $1,503,142 $1,567,364 $3,800 ($1,447,979 ) $1,626,327 Liabilities and Shareholders’ Equity Current liabilities $114,805 $2,822,729 $3,800 ($2,729,375 ) $211,959 Long-term liabilities 1,348,105 26,927 — 15,878 1,390,910 Total shareholders’ equity 40,232 (1,282,292 ) — 1,265,518 23,458 Total Liabilities and Shareholders’ Equity $1,503,142 $1,567,364 $3,800 ($1,447,979 ) $1,626,327 CARRIZO OIL & GAS, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (In thousands) (Unaudited) Three Months Ended March 31, 2017 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Total revenues $82 $151,273 $— $— $151,355 Total costs and expenses 18,868 92,456 — 10 111,334 Income (loss) before income taxes (18,786 ) 58,817 — (10 ) 40,021 Income tax expense — — — — — Equity in income of subsidiaries 58,817 — — (58,817 ) — Net income $40,031 $58,817 $— ($58,827 ) $40,021 Three Months Ended March 31, 2016 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Total revenues $115 $81,147 $— $— $81,262 Total costs and expenses 29,912 362,248 — 376 392,536 Loss before income taxes (29,797 ) (281,101 ) — (376 ) (311,274 ) Income tax expense — — — (121 ) (121 ) Equity in loss of subsidiaries (281,101 ) — — 281,101 — Net loss ($310,898 ) ($281,101 ) $— $280,604 ($311,395 ) CARRIZO OIL & GAS, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (In thousands) (Unaudited) Three Months Ended March 31, 2017 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Total revenues $82 $151,273 $— $— $151,355 Total costs and expenses 18,868 92,456 — 10 111,334 Income (loss) before income taxes (18,786 ) 58,817 — (10 ) 40,021 Income tax benefit — — — — — Equity in loss of subsidiaries 58,817 — — (58,817 ) — Net income (loss) $40,031 $58,817 $— ($58,827 ) $40,021 Three Months Ended March 31, 2016 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Total revenues $115 $81,147 $— $— $81,262 Total costs and expenses 29,912 362,248 — 376 392,536 Loss before income taxes (29,797 ) (281,101 ) — (376 ) (311,274 ) Income tax expense — — — (121 ) (121 ) Equity in loss of subsidiaries (281,101 ) — — 281,101 — Net loss ($310,898 ) ($281,101 ) $— $280,604 ($311,395 ) CARRIZO OIL & GAS, INC. CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (In thousands) (Unaudited) Three Months Ended March 31, 2017 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Net cash provided by (used in) operating activities ($47,297 ) $123,705 $— $— $76,408 Net cash provided by (used in) investing activities 9,879 (114,212 ) — (9,493 ) (113,826 ) Net cash provided by (used in) financing activities 35,615 (9,493 ) — 9,493 35,615 Net decrease in cash and cash equivalents (1,803 ) — — — (1,803 ) Cash and cash equivalents, beginning of period 4,194 — — — 4,194 Cash and cash equivalents, end of period $2,391 $— $— $— $2,391 Three Months Ended March 31, 2016 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Net cash provided by (used in) operating activities ($2,156 ) $56,024 $— $— $53,868 Net cash used in investing activities (68,797 ) (122,849 ) (740 ) 67,565 (124,821 ) Net cash provided by financing activities 30,193 66,825 740 (67,565 ) 30,193 Net decrease in cash and cash equivalents (40,760 ) — — — (40,760 ) Cash and cash equivalents, beginning of period 42,918 — — — 42,918 Cash and cash equivalents, end of period $2,158 $— $— $— $2,158

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	3 Months Ended
	Mar. 31, 2017
Supplemental Cash Flow Elements [Abstract]
Cash Flow, Supplemental Disclosures	12. Supplemental Cash Flow Information Supplemental cash flow disclosures and non-cash investing activities are presented below: Three Months Ended 2017 2016 (In thousands) Supplemental cash flow disclosures: Cash paid for interest, net of amounts capitalized $19,480 $17,553 Cash paid for income taxes — — Non-cash investing activities: Increase (decrease) in capital expenditure payables and accruals $28,139 ($27,989 ) Stock-based compensation expense capitalized to oil and gas properties 855 1,920 Asset retirement obligations capitalized to oil and gas properties 447 518 Other non-cash investing activities 343 1,485

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2017
Subsequent Events [Abstract]
Subsequent Events	13. Subsequent Events Hedging In April 2017, the Company entered into the following crude oil derivative positions: Period Type of Contract Crude Oil Volumes (in Bbls/d) Weighted Average Sub-Floor Price ($/Bbl) Weighted Average Floor Price ($/Bbl) Weighted Average Ceiling Price ($/Bbl) Q3 2017 Fixed Price Swaps 6,000 $53.28 Q4 2017 Fixed Price Swaps 6,000 $53.28 FY 2018 Three-Way Collars 6,000 $40.00 $50.00 $65.00 In order to obtain a higher weighted average ceiling price on the three-way collars, the Company incurred premiums of approximately $2.8 million , the payments for which are deferred until the applicable contracts settle on a monthly basis. Sanchez Acquisition In April 2017, the Company paid $9.8 million for the remaining outstanding leases that were not conveyed to the Company at the initial closing on December 14, 2016 or at the subsequent closing on January 9, 2017. The Company currently expects its allocation of the purchase price to the assets acquired and liabilities assumed as of the acquisition date will be finalized during the fourth quarter of 2017. Ninth Amendment to Credit Agreement On May 4, 2017, the Company entered into a ninth amendment to its credit agreement governing the revolving credit facility to, among other things (i) extend the maturity date of the revolving credit facility to May 4, 2022, subject to a springing maturity date of June 15, 2020 if the 7.50% Senior Notes have not been refinanced on or prior to such time, (ii) increase the maximum credit amount under the revolving credit facility from $1.0 billion to $2.0 billion , (iii) increase the borrowing base from $600.0 million to $900.0 million , of which $800.0 million has been committed by lenders, until the next redetermination thereof, (iv) replace the Total Secured Debt to EBITDA ratio covenant with a Total Debt to EBITDA ratio covenant that requires such ratio not to exceed 4.00 to 1.00, (v) remove the covenant requiring a minimum EBITDA to Interest Expense ratio, (vi) reduce the commitment fee from 0.50% to 0.375% when utilization of lender commitments is less than 50% of the borrowing base amount, (vii) remove the restriction from borrowing under the credit facility if the Company has or, after giving effect to the borrowing, will have a Consolidated Cash Balance in excess of $50.0 million , (viii) remove the mandatory repayment of borrowings to the extent the Consolidated Cash Balance exceeds $50.0 million if either (a) the Company’s ratio of Total Debt to EBITDA exceeds 3.50 to 1.00 or (b) the availability under the credit facility is equal to or less than 20% of the then effective borrowing base, (ix) permit the issuance of unlimited Senior Unsecured Debt, subject to certain conditions, including pro forma compliance with the Company’s financial covenants, and (x) increase certain covenant baskets and thresholds. The capitalized terms which are not defined in this note to the consolidated financial statements have the meaning given to such terms in the credit agreement.

Summary of Significant Accoun20

Summary of Significant Accounting Policies (Policy)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
New Accounting Pronouncements	Recently Adopted Accounting Pronouncement In March 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”), which amends certain aspects of accounting for share-based payment arrangements. ASU 2016-09 revises or provides alternative accounting for the tax impacts of share-based payment arrangements, forfeitures, minimum statutory tax withholdings, and prescribes certain disclosures to be made in the period of adoption. Effective January, 1, 2017, the Company adopted ASU 2016-09. Using the modified retrospective approach as prescribed by ASU 2016-09, the Company recognized previously unrecognized windfall tax benefits which resulted in a cumulative-effect adjustment to retained earnings of approximately $15.7 million . This adjustment increased deferred tax assets, which in turn increased the valuation allowance by the same amount as of the beginning of 2017, resulting in a net cumulative-effect adjustment to retained earnings of zero. As a result of adoption, on a prospective basis as prescribed by ASU 2016-09, all windfall tax benefits and tax shortfalls will be recorded as income tax expense or benefit in the consolidated statements of operations. As long as the Company continues to conclude that the valuation allowance against its net deferred tax assets is necessary, this portion of ASU 2016-09 will have no significant effect on the Company’s consolidated balance sheets or consolidated statements of operations. In addition, windfall tax benefits are now required to be presented in cash flows from operating activities in the consolidated statements of cash flows as compared to cash flows from financing activities, which the Company has elected to adopt prospectively. There are no periods presented that would require reclassification of cash flows had the Company elected to adopt this guidance retrospectively. Further, the Company has elected to account for forfeitures as they occur, which resulted in an immaterial cumulative-effect adjustment to retained earnings. Recently Issued Accounting Pronouncements In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (“ASU 2016-15”), which is intended to reduce diversity in practice in how certain transactions are classified in the statement of cash flows. The guidance addresses eight specific cash flow issues for which current GAAP is either unclear or does not include specific guidance. ASU 2016-15 is effective for interim and annual periods beginning after December 15, 2017, with early adoption permitted, provided that it is adopted in its entirety in the same period. Currently, the Company does not expect the impact of adopting ASU 2016-15 to have a material effect on its consolidated statements of cash flows. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), which significantly changes accounting for leases by requiring that lessees recognize a right-of-use asset and a related lease liability representing the obligation to make lease payments, for virtually all lease transactions. Additional disclosures about an entity’s lease transactions will also be required. ASU 2016-02 defines a lease as “a contract, or part of a contract, that conveys the right to control the use of identified property, plant or equipment (an identified asset) for a period of time in exchange for consideration.” ASU 2016-02 is effective for interim and annual periods beginning after December 15, 2018 with early adoption permitted. ASU 2016-02 requires companies to recognize and measure leases at the beginning of the earliest period presented in the financial statements using a modified retrospective approach. Although the Company is in the process of evaluating ASU 2016-02 and the impact the adoption of the new standard will have on its consolidated financial statements and related disclosures, it is currently anticipated to result in an increase in the assets and liabilities recorded on its consolidated balance sheets. The Company will evaluate its existing contracts including, but not limited to, drilling rig contracts and gathering, processing, and transportation contracts to determine if they qualify for lease accounting under ASU 2016-02. In May 2014, the FASB issued ASU No. 2014-09, Revenue From Contracts With Customers (Topic 606) (“ASU 2014-09”), which will require entities to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 will supersede most current guidance related to revenue recognition when it becomes effective. The new standard also will require expanded disclosures regarding the nature, timing, amount and certainty of revenue and cash flows from contracts with customers. ASU 2014-09 is effective for interim and annual periods beginning after December 15, 2017 with early adoption permitted for interim and annual periods beginning after December 31, 2016. Companies are permitted to adopt ASU 2014-09 through the use of either the full retrospective approach, meaning the standard is applied to all of the periods presented, or a modified retrospective approach, meaning the cumulative effect of initially applying the standard is recognized in the most current period presented in the financial statements. The Company is in the process of assessing the impact of ASU 2014-09 with the assistance of an outside consultant. The assessment consists of analyzing the Company’s existing contracts and current accounting policies and practices to identify potential differences that would result from applying the requirements of ASU 2014-09. Once the assessment is complete, the Company will implement appropriate changes to its business processes, systems or controls to support recognition and disclosure pursuant to ASU 2014-09. Based on assessments performed to date, the Company currently does not expect the impact of adopting ASU 2014-09 to have a material effect on the timing or method of revenue recognition as the performance obligations are not materially changed under ASU 2014-09. The Company currently plans to apply the modified retrospective method upon adoption and plans to adopt the guidance on the effective date of January 1, 2018, however, the Company continues to review the impact of ASU 2014-09 on its consolidated financial statements and related disclosures.

Summary of Significant Accoun21

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Schedule of Supplemental Net Income Per Common Share	Supplemental net income (loss) per common share information is provided below: Three Months Ended 2017 2016 (In thousands, except per share amounts) Net Income (Loss) $40,021 ($311,395 ) Basic weighted average common shares outstanding 65,188 58,360 Effect of dilutive instruments 590 — Diluted weighted average common shares outstanding 65,778 58,360 Net Income (Loss) Per Common Share Basic $0.61 ($5.34 ) Diluted $0.61 ($5.34 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The table below presents the dilutive and anti-dilutive weighted average common shares outstanding for the three months ended March 31, 2017 and 2016 : Three Months Ended 2017 2016 (In thousands) Dilutive 590 — Anti-dilutive (1) 5 665 (1) For the three months ended March 31, 2016 , the Company reported a net loss. As a result, all potentially dilutive common shares outstanding were anti-dilutive.

Acquisitions (Tables)

Acquisitions (Tables)	3 Months Ended
	Mar. 31, 2017
Schedule of Consideration Paid for the Transactions of Assets Acquired and Liabilities Assumed [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The following presents the purchase price and the preliminary allocation of the purchase price to the assets acquired and liabilities assumed as of the acquisition date. The Company currently expects these amounts will be finalized during the fourth quarter of 2017. Preliminary Purchase Price Allocation (In thousands) Assets Other current assets $477 Oil and gas properties Proved properties 94,664 Unproved properties 70,309 Total oil and gas properties 164,973 Total assets acquired $165,450 Liabilities Revenues and royalties payable $1,442 Other current liabilities 323 Asset retirement obligations 2,054 Other liabilities 1,078 Total liabilities assumed $4,897 Net Assets Acquired $160,553

Property And Equipment, Net (Ta

Property And Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2017
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment	As of March 31, 2017 and December 31, 2016 , total property and equipment, net consisted of the following: March 31, December 31, (In thousands) Oil and gas properties, full cost method Proved properties $4,817,044 $4,687,416 Accumulated depreciation, depletion and amortization and impairments (3,445,709 ) (3,392,749 ) Proved properties, net 1,371,335 1,294,667 Unproved properties, not being amortized Unevaluated leasehold and seismic costs 221,039 211,067 Capitalized interest 32,231 29,894 Total unproved properties, not being amortized 253,270 240,961 Other property and equipment 23,240 23,127 Accumulated depreciation (13,641 ) (12,995 ) Other property and equipment, net 9,599 10,132 Total property and equipment, net $1,634,204 $1,545,760
Schedule of Impairment of Oil and Gas Properties	Details of the 12-Month Average Realized Price of crude oil for the three months ended March 31, 2017 and 2016 and the impairment of proved oil and gas properties for the three months ended March 31, 2016 are summarized in the table below: Three Months Ended 2017 2016 Impairment of proved oil and gas properties (in thousands) $— $274,413 Crude Oil 12-Month Average Realized Price ($/Bbl) - Beginning of period $39.60 $47.24 Crude Oil 12-Month Average Realized Price ($/Bbl) - End of period $44.98 $43.13 Percentage increase (decrease) 14 % (9 %)

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Schedule Of Effective Income Tax Rate Reconciliation	The Company’s income tax (expense) benefit differs from the income tax (expense) benefit computed by applying the U.S. federal statutory corporate income tax rate of 35% to income (loss) before income taxes as follows: Three Months Ended 2017 2016 (In thousands) Income (loss) before income taxes $40,021 ($311,274 ) Income tax (expense) benefit at the statutory rate (14,007 ) 108,946 State income tax (expense) benefit, net of U.S. federal income taxes (710 ) 1,619 Tax shortfalls from stock-based compensation expense (2,592 ) — Deferred tax assets valuation allowance 17,369 (110,679 ) Other (60 ) (7 ) Income tax expense $— ($121 )

Long-Term Debt (Tables)

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Long-term debt consisted of the following as of March 31, 2017 and December 31, 2016 : March 31, December 31, (In thousands) Senior Secured Revolving Credit Facility due 2018 $123,000 $87,000 7.50% Senior Notes due 2020 600,000 600,000 Unamortized premium for 7.50% Senior Notes 960 1,020 Unamortized debt issuance costs for 7.50% Senior Notes (7,189 ) (7,573 ) 6.25% Senior Notes due 2023 650,000 650,000 Unamortized debt issuance costs for 6.25% Senior Notes (9,150 ) (9,454 ) Other long-term debt due 2028 4,425 4,425 Long-term debt $1,362,046 $1,325,418
Interest and Commitment Fee Rates	Borrowings outstanding under the credit agreement bear interest at the Company’s option at either (i) a base rate for a base rate loan plus the margin set forth in the table below, where the base rate is defined as the greatest of the prime rate, the federal funds rate plus 0.50% and the adjusted LIBO rate plus 1.00% , or (ii) an adjusted LIBO rate for a Eurodollar loan plus the margin set forth in the table below. The Company also incurs commitment fees at rates, as of March 31, 2017, as set forth in the table below on the unused portion of lender commitments, which are included in interest expense, net in the consolidated statements of operations. Ratio of Outstanding Borrowings and Letters of Credit to Lender Commitments Applicable Margin for Base Rate Loans Applicable Margin for Eurodollar Loans Commitment Fee Less than 25% 1.00% 2.00% 0.500% Greater than or equal to 25% but less than 50% 1.25% 2.25% 0.500% Greater than or equal to 50% but less than 75% 1.50% 2.50% 0.500% Greater than or equal to 75% but less than 90% 1.75% 2.75% 0.500% Greater than or equal to 90% 2.00% 3.00% 0.500%

Shareholders' Equity and Stoc26

Shareholders' Equity and Stock Incentive Plans (Tables)	3 Months Ended
	Mar. 31, 2017
Shareholders' Equity and Stock Incentive Plans [Abstract]
Schedule of Restricted Stock Awards and Restricted Stock Units Activity	The table below summarizes restricted stock award and unit activity for the first quarter of 2017: Restricted Stock Awards and Units Weighted Average Grant Date Fair Value For the Three Months Ended March 31, 2017 Unvested restricted stock awards and units, beginning of period 1,111,710 $36.93 Granted 749,396 $27.07 Vested (569,145 ) $39.48 Forfeited (3,933 ) $29.42 Unvested restricted stock awards and units, end of period 1,288,028 $30.09
Schedule of Stock Appreciation Rights Award Activity	The table below summarizes the activity for SARs for the first quarter of 2017: Stock Appreciation Rights Weighted Average Exercise Prices Weighted Average Remaining Life (In years) Aggregate Intrinsic Value (In millions) Aggregate Intrinsic Value of Exercises (In millions) For the Three Months Ended March 31, 2017 Outstanding, beginning of period 722,638 $23.69 Granted 342,440 $26.94 Exercised (100,000 ) $17.28 $1.3 Forfeited — — Outstanding, end of period 965,078 $25.51 3.4 $2.5 Exercisable, end of period 436,739 $23.62 1.8 $2.0
Schedule of Stock Appreciation Rights Valuation Assumptions	The following table summarizes the assumptions used to calculate the grant date fair value of SARs granted during the first quarter of 2017 : Grant Date Fair Value Assumptions Expected term (in years) 4.24 Expected volatility 54.3 % Risk-free interest rate 1.8 % Dividend yield — % Grant date fair value $12.00
Schedule of Performance Shares Award Unvested Activity	The table below summarizes performance share activity for the first quarter of 2017 : Performance Shares Weighted Average Grant Date Fair Value For the Three Months Ended March 31, 2017 Unvested performance shares, beginning of period 154,510 $58.44 Granted 46,787 $35.14 Vested (1) (56,342 ) $68.15 Forfeited — — Unvested performance shares, end of period 144,955 $47.14
Schedule of Performance Share Award Valuation Assumptions	The following table summarizes the assumptions used to calculate the grant date fair value of the performance shares granted during the first quarter of 2017 : Grant Date Fair Value Assumptions Number of simulations 500,000 Expected term (in years) 2.98 Expected volatility 59.2 % Risk-free interest rate 1.5 % Dividend yield — % Grant date fair value $35.14
Schedule of Stock-based Compensation, net	The Company recognized the following stock-based compensation expense, net for the periods indicated: Three Months Ended 2017 2016 (In thousands) Restricted stock awards and units $5,849 $11,594 Stock appreciation rights (3,686 ) 1,232 Performance shares 706 616 2,869 13,442 Less: amounts capitalized to oil and gas properties (855 ) (1,920 ) Total stock-based compensation expense, net $2,014 $11,522

Derivative Instruments (Tables)

Derivative Instruments (Tables)	3 Months Ended
	Mar. 31, 2017
Derivative [Line Items]
Schedule of Derivative Instruments in Statement of Financial Position	The combined derivative instrument fair value assets and liabilities recorded in the Company’s consolidated balance sheets as of March 31, 2017 and December 31, 2016 are summarized below: March 31, 2017 Gross Amounts Recognized Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts Presented in the Consolidated Balance Sheets (In thousands) Derivative assets Derivative assets-current $2,417 ($1,381 ) $1,036 Derivative assets-non current 106 (106 ) — Derivative liabilities Derivative liabilities-current (8,837 ) 1,381 (7,456 ) Derivative liabilities-non current (18,781 ) 106 (18,675 ) Total ($25,095 ) $— ($25,095 ) December 31, 2016 Gross Amounts Recognized Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts Presented in the Consolidated Balance Sheets (In thousands) Derivative assets Derivative assets-current $6,507 ($5,270 ) $1,237 Derivative assets-non current 1,313 (1,313 ) — Derivative liabilities Derivative liabilities-current (27,871 ) 5,270 (22,601 ) Derivative liabilities-non current (28,841 ) 1,313 (27,528 ) Total ($48,892 ) $— ($48,892 )
Schedule of (Gain) Loss on Derivative Instruments	The effect of derivative instruments on the Company’s consolidated statements of operations for the three months ended March 31, 2017 and 2016 by commodity is summarized below: Three Months Ended 2017 2016 (In thousands) (Gain) Loss on Derivatives, Net Crude oil ($18,480 ) ($21,891 ) Natural gas (6,836 ) 11,338 Total (Gain) Loss on Derivatives, Net ($25,316 ) ($10,553 )
Crude Oil [Member]
Derivative [Line Items]
Schedule of Derivative Instruments	The following sets forth a summary of the Company’s crude oil derivative positions at average NYMEX prices as of March 31, 2017 : Period Type of Contract Crude Oil Volumes (in Bbls/d) Weighted Average Floor Price ($/Bbl) Weighted Average Ceiling Price ($/Bbl) Q2 2017 Fixed Price Swaps 12,000 $50.13 Q3 2017 Fixed Price Swaps 6,000 $54.15 Q4 2017 Fixed Price Swaps 3,000 $55.01 FY 2018 Sold Call Options 2,488 $60.00 FY 2018 Net Sold Call Options 900 $75.00 FY 2019 Sold Call Options 2,975 $62.50 FY 2019 Net Sold Call Options 900 $77.50 FY 2020 Sold Call Options 3,675 $65.00 FY 2020 Net Sold Call Options 900 $80.00 In April 2017, the Company entered into the following crude oil derivative positions: Period Type of Contract Crude Oil Volumes (in Bbls/d) Weighted Average Sub-Floor Price ($/Bbl) Weighted Average Floor Price ($/Bbl) Weighted Average Ceiling Price ($/Bbl) Q3 2017 Fixed Price Swaps 6,000 $53.28 Q4 2017 Fixed Price Swaps 6,000 $53.28 FY 2018 Three-Way Collars 6,000 $40.00 $50.00 $65.00
Natural Gas Derivative Positions [Member]
Derivative [Line Items]
Schedule of Derivative Instruments	The following sets forth a summary of the Company’s natural gas derivative positions at average NYMEX prices as of March 31, 2017 : Period Type of Contract Natural Gas Volumes Weighted Average Floor Price ($/MMBtu) Weighted Q2 - Q4 2017 Fixed Price Swaps 20,000 $3.30 Q2 - Q4 2017 Sold Call Options 33,000 $3.00 FY 2018 Sold Call Options 33,000 $3.25 FY 2019 Sold Call Options 33,000 $3.25 FY 2020 Sold Call Options 33,000 $3.50

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables summarize the Company’s assets and liabilities measured at fair value on a recurring basis as of March 31, 2017 and December 31, 2016 : March 31, 2017 Level 1 Level 2 Level 3 (In thousands) Derivative assets $— $1,036 $— Derivative liabilities $— ($21,970 ) $— December 31, 2016 Level 1 Level 2 Level 3 (In thousands) Derivative assets $— $1,237 $— Derivative liabilities $— ($45,552 ) $—
Schedule of Carrying Value and Estimated Fair Value of Debt Instruments	The following table presents the carrying amounts of the Company’s senior notes and other long-term debt, net of debt premiums and debt issuance costs, with the fair values measured using Level 1 inputs based on quoted secondary market trading prices. March 31, 2017 December 31, 2016 Carrying Amount Fair Value Carrying Amount Fair Value (In thousands) 7.50% Senior Notes due 2020 $593,771 $616,500 $593,447 $624,750 6.25% Senior Notes due 2023 640,850 650,000 640,546 672,750 Other long-term debt due 2028 4,425 4,425 4,425 4,419

Condensed Consolidating Finan29

Condensed Consolidating Financial Information (Tables)	3 Months Ended
	Mar. 31, 2017
Condensed Consolidating Financial Information [Abstract]
Schedule Of Condensed Consolidating Balance Sheets	CARRIZO OIL & GAS, INC. CONDENSED CONSOLIDATING BALANCE SHEETS (In thousands) (Unaudited) March 31, 2017 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Assets Total current assets $2,724,856 $66,199 $— ($2,717,829 ) $73,226 Total property and equipment, net 41,196 1,593,134 3,800 (3,926 ) 1,634,204 Investment in subsidiaries (1,223,475 ) — — 1,223,475 — Other assets 6,855 155 — — 7,010 Total Assets $1,549,432 $1,659,488 $3,800 ($1,498,280 ) $1,714,440 Liabilities and Shareholders’ Equity Current liabilities $90,083 $2,854,994 $3,800 ($2,720,849 ) $228,028 Long-term liabilities 1,372,638 27,969 — 15,878 1,416,485 Total shareholders’ equity 86,711 (1,223,475 ) — 1,206,691 69,927 Total Liabilities and Shareholders’ Equity $1,549,432 $1,659,488 $3,800 ($1,498,280 ) $1,714,440 December 31, 2016 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Assets Total current assets $2,735,830 $63,513 $— ($2,726,355 ) $72,988 Total property and equipment, net 42,181 1,503,695 3,800 (3,916 ) 1,545,760 Investment in subsidiaries (1,282,292 ) — — 1,282,292 — Other assets 7,423 156 — — 7,579 Total Assets $1,503,142 $1,567,364 $3,800 ($1,447,979 ) $1,626,327 Liabilities and Shareholders’ Equity Current liabilities $114,805 $2,822,729 $3,800 ($2,729,375 ) $211,959 Long-term liabilities 1,348,105 26,927 — 15,878 1,390,910 Total shareholders’ equity 40,232 (1,282,292 ) — 1,265,518 23,458 Total Liabilities and Shareholders’ Equity $1,503,142 $1,567,364 $3,800 ($1,447,979 ) $1,626,327
Schedule Of Condensed Consolidating Statements Of Operations	CARRIZO OIL & GAS, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (In thousands) (Unaudited) Three Months Ended March 31, 2017 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Total revenues $82 $151,273 $— $— $151,355 Total costs and expenses 18,868 92,456 — 10 111,334 Income (loss) before income taxes (18,786 ) 58,817 — (10 ) 40,021 Income tax expense — — — — — Equity in income of subsidiaries 58,817 — — (58,817 ) — Net income $40,031 $58,817 $— ($58,827 ) $40,021 Three Months Ended March 31, 2016 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Total revenues $115 $81,147 $— $— $81,262 Total costs and expenses 29,912 362,248 — 376 392,536 Loss before income taxes (29,797 ) (281,101 ) — (376 ) (311,274 ) Income tax expense — — — (121 ) (121 ) Equity in loss of subsidiaries (281,101 ) — — 281,101 — Net loss ($310,898 ) ($281,101 ) $— $280,604 ($311,395 ) CARRIZO OIL & GAS, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (In thousands) (Unaudited) Three Months Ended March 31, 2017 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Total revenues $82 $151,273 $— $— $151,355 Total costs and expenses 18,868 92,456 — 10 111,334 Income (loss) before income taxes (18,786 ) 58,817 — (10 ) 40,021 Income tax benefit — — — — — Equity in loss of subsidiaries 58,817 — — (58,817 ) — Net income (loss) $40,031 $58,817 $— ($58,827 ) $40,021 Three Months Ended March 31, 2016 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Total revenues $115 $81,147 $— $— $81,262 Total costs and expenses 29,912 362,248 — 376 392,536 Loss before income taxes (29,797 ) (281,101 ) — (376 ) (311,274 ) Income tax expense — — — (121 ) (121 ) Equity in loss of subsidiaries (281,101 ) — — 281,101 — Net loss ($310,898 ) ($281,101 ) $— $280,604 ($311,395 )
Schedule Of Condensed Consolidating Statements Of Cash Flows	CARRIZO OIL & GAS, INC. CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (In thousands) (Unaudited) Three Months Ended March 31, 2017 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Net cash provided by (used in) operating activities ($47,297 ) $123,705 $— $— $76,408 Net cash provided by (used in) investing activities 9,879 (114,212 ) — (9,493 ) (113,826 ) Net cash provided by (used in) financing activities 35,615 (9,493 ) — 9,493 35,615 Net decrease in cash and cash equivalents (1,803 ) — — — (1,803 ) Cash and cash equivalents, beginning of period 4,194 — — — 4,194 Cash and cash equivalents, end of period $2,391 $— $— $— $2,391 Three Months Ended March 31, 2016 Parent Company Combined Guarantor Subsidiaries Combined Non- Guarantor Subsidiaries Eliminations Consolidated Net cash provided by (used in) operating activities ($2,156 ) $56,024 $— $— $53,868 Net cash used in investing activities (68,797 ) (122,849 ) (740 ) 67,565 (124,821 ) Net cash provided by financing activities 30,193 66,825 740 (67,565 ) 30,193 Net decrease in cash and cash equivalents (40,760 ) — — — (40,760 ) Cash and cash equivalents, beginning of period 42,918 — — — 42,918 Cash and cash equivalents, end of period $2,158 $— $— $— $2,158

Supplemental Cash Flow Inform30

Supplemental Cash Flow Information (Tables)	3 Months Ended
	Mar. 31, 2017
Supplemental Cash Flow Elements [Abstract]
Schedule of Cash Flow, Supplemental Disclosures	Three Months Ended 2017 2016 (In thousands) Supplemental cash flow disclosures: Cash paid for interest, net of amounts capitalized $19,480 $17,553 Cash paid for income taxes — — Non-cash investing activities: Increase (decrease) in capital expenditure payables and accruals $28,139 ($27,989 ) Stock-based compensation expense capitalized to oil and gas properties 855 1,920 Asset retirement obligations capitalized to oil and gas properties 447 518 Other non-cash investing activities 343 1,485

Subsequent Events (Tables)

Subsequent Events (Tables)	3 Months Ended
	Mar. 31, 2017
Crude Oil [Member]
Derivative [Line Items]
Schedule of Derivative Instruments	The following sets forth a summary of the Company’s crude oil derivative positions at average NYMEX prices as of March 31, 2017 : Period Type of Contract Crude Oil Volumes (in Bbls/d) Weighted Average Floor Price ($/Bbl) Weighted Average Ceiling Price ($/Bbl) Q2 2017 Fixed Price Swaps 12,000 $50.13 Q3 2017 Fixed Price Swaps 6,000 $54.15 Q4 2017 Fixed Price Swaps 3,000 $55.01 FY 2018 Sold Call Options 2,488 $60.00 FY 2018 Net Sold Call Options 900 $75.00 FY 2019 Sold Call Options 2,975 $62.50 FY 2019 Net Sold Call Options 900 $77.50 FY 2020 Sold Call Options 3,675 $65.00 FY 2020 Net Sold Call Options 900 $80.00 In April 2017, the Company entered into the following crude oil derivative positions: Period Type of Contract Crude Oil Volumes (in Bbls/d) Weighted Average Sub-Floor Price ($/Bbl) Weighted Average Floor Price ($/Bbl) Weighted Average Ceiling Price ($/Bbl) Q3 2017 Fixed Price Swaps 6,000 $53.28 Q4 2017 Fixed Price Swaps 6,000 $53.28 FY 2018 Three-Way Collars 6,000 $40.00 $50.00 $65.00

Summary of Significant Accoun32

Summary of Significant Accounting Policies (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)
Summary Of Significant Accounting Policies [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions	$ 15.7

Summary of Significant Accoun33

Summary of Significant Accounting Policies (Schedule of Earnings Per Share Reconciliation) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net Income (Loss)	$ 40,021	$ (311,395)
Basic weighted average common shares outstanding	65,188	58,360
Effect of dilutive instruments	590	0
Diluted weighted average common shares outstanding	65,778	58,360
Net Income (Loss) - basic (in dollars per share)	$ 0.61	$ (5.34)
Net Income (Loss) - diluted (in dollars per share)	$ 0.61	$ (5.34)

Summary of Significant Accoun34

Summary of Significant Accounting Policies (Schedule of Antidilutive Shares Excluded from Earnings Per Share) (Details) - shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Effect of dilutive instruments	590,000	0
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	5,000	665,000

Acquisitions (Narrative) (Detai

Acquisitions (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Apr. 30, 2017	Mar. 31, 2017	Mar. 31, 2016	Dec. 14, 2016
Business Acquisition [Line Items]
Deferred Purchase Price				$ 16,800
Payments to acquire oil and gas property		$ 7,032	$ 0
Subsequent Event [Member]
Business Acquisition [Line Items]
Payments to acquire oil and gas property	$ 9,800

Acquisitions (Schedule of Consi

Acquisitions (Schedule of Consideration Paid for Assets Acquired and Liabilities Assumed) (Table) (Details) $ in Thousands	Dec. 14, 2016USD ($)
Acquisitions - Schedule of Consideration Paid for the Transactions of Assets Acquired and Liabilities Assumed [Abstract]
Business Combination, Current Assets	$ 477
Business Combination, Proved Oil and Gas Properties	94,664
Business Combination, Unproved Oil and Gas Properties	70,309
Business Combination, Oil and Gas Properties	164,973
Business Combination, Assets	165,450
Business Combination, Current Liabilities	1,442
Business Combination, Current Liabilities, Other	323
Business Combination, Noncurrent Liabilities	2,054
Business Combination, Noncurrent Liabilities, Other	1,078
Business Combination, Liabilities	4,897
Business Combination, Assets Acquired and Liabilities Assumed, Net	$ 160,553

Property and Equipment, Net (Na

Property and Equipment, Net (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)$ / Boe	Mar. 31, 2016USD ($)$ / Boe
Property, Plant and Equipment [Line Items]
Average depreciation, depletion and amortization, per Boe | $ / Boe	12.69	15.22
Internal costs capitalized, Oil and Gas producing activities	$ 5,400	$ 4,400
Capitalized interest	3,800	5,600
Proceeds from sales of oil and gas properties, net	$ 17,372	$ 1,785
Reserves discount factor	10.00%
Delaware Basin [Member]
Property, Plant and Equipment [Line Items]
Proceeds from sales of oil and gas properties, net	$ 15,300

Property And Equipment, Net (Sc

Property And Equipment, Net (Schedule Of Property And Equipment) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Proved properties	$ 4,817,044	$ 4,687,416
Accumulated depreciation, depletion and amortization and impairments	(3,445,709)	(3,392,749)
Proved properties, net	1,371,335	1,294,667
Unproved properties, not being amortized
Unevaluated leasehold and seismic costs	221,039	211,067
Exploratory wells in progress	0	0
Capitalized interest	32,231	29,894
Total unproved properties, not being amortized	253,270	240,961
Other property and equipment	23,240	23,127
Accumulated depreciation	(13,641)	(12,995)
Other property and equipment, net	9,599	10,132
Total property and equipment, net	$ 1,634,204	$ 1,545,760

Property and Equipment, Net (39

Property and Equipment, Net (Schedule of Impairment of Oil and Gas Properties) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)$ / bbls	Mar. 31, 2016USD ($)$ / bbls	Dec. 31, 2016$ / bbls	Dec. 31, 2015$ / bbls
Impairment Of Oil And Gas Properties [Line Items]
Impairment of proved oil and gas properties | $	$ 0	$ 274,413
Change in price used in ceiling test calculation	14.00%	(9.00%)
Crude Oil [Member]
Impairment Of Oil And Gas Properties [Line Items]
Average Realized Price | $ / bbls	44.98	43.13	39.60	47.24

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Jan. 01, 2017
Income Taxes [Line Items]
U.S. federal statutory corporate pretax rate	35.00%
Deferred Tax Assets, Net	$ 0
Tax Adjustments, Settlements, and Unusual Provisions	15,700
Deferred Tax Assets, Valuation Allowance	(562,720)		$ (580,100)
Deferred Tax Assets, (Increase) Decrease in Valuation Allowance	$ 17,369	$ (110,679)

Income Taxes (Schedule Of Effec

Income Taxes (Schedule Of Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income (loss) before income taxes	$ 40,021	$ (311,274)
Income tax (expense) benefit at the statutory rate	(14,007)	108,946
State income tax (expense) benefit, net of U.S. federal income taxes	(710)	1,619
Tax shortfalls from stock-based compensation expense	(2,592)	0
Deferred tax assets valuation allowance	17,369	(110,679)
Other	(60)	(7)
Income tax (expense) benefit	$ 0	$ (121)

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	May 04, 2017	Dec. 31, 2016
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 600,000,000
Line of credit facility amount outstanding	$ 123,000,000		$ 87,000,000
Debt, Weighted Average Interest Rate	2.95%
Letters of credit outstanding amount	$ 415,000
Pre-Tax SEC PV10 Reserve Value Percentage	90.00%
Federal funds rate plus percentage	0.50%
Adjusted LIBO rate plus percentage	1.00%
Ratio of Total Secured Debt to EBITDA	0.30
Current Ratio	2.56
Ratio of EBITDA to Interest Expense	4.53
Senior Secured Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Ratio of Total Secured Debt to EBITDA	2
Senior Secured Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Current Ratio	1
Ratio of EBITDA to Interest Expense	2.50
6.25% Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 650,000,000		650,000,000
7.50% Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.50%
Long term debt	$ 600,000,000		$ 600,000,000
Subsequent Event [Member] | Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity		$ 900,000,000

Long-Term Debt (Schedule of Lon

Long-Term Debt (Schedule of Long-Term Debt) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt	$ 1,362,046	$ 1,325,418
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility amount outstanding	123,000	87,000
7.50% Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	600,000	600,000
Debt instrument, unamortized premium	960	1,020
Unamortized Debt Issuance Expense	(7,189)	(7,573)
6.25% Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	650,000	650,000
Unamortized Debt Issuance Expense	(9,150)	(9,454)
Other Long Term Debt [Member]
Debt Instrument [Line Items]
Long term debt	$ 4,425	$ 4,425

Long-Term Debt (Interest and Co

Long-Term Debt (Interest and Commitment Fee Rates) (Details)	3 Months Ended
	Mar. 31, 2017
Less than 25 percent [Member]
Interest and Commitment Fee Rates [Line Items]
Margin for base rate loans	1.00%
Margin for eurodollar loans	2.00%
Line of Credit Facility, Commitment Fee Percentage	0.50%
Greater than or equal to 25 percent but less than 50 percent [Member]
Interest and Commitment Fee Rates [Line Items]
Margin for base rate loans	1.25%
Margin for eurodollar loans	2.25%
Line of Credit Facility, Commitment Fee Percentage	0.50%
Greater than or equal to 50 percent but less than 75 percent [Member]
Interest and Commitment Fee Rates [Line Items]
Margin for base rate loans	1.50%
Margin for eurodollar loans	2.50%
Line of Credit Facility, Commitment Fee Percentage	0.50%
Greater than or equal to 75 percent but less than 90 percent [Member]
Interest and Commitment Fee Rates [Line Items]
Margin for base rate loans	1.75%
Margin for eurodollar loans	2.75%
Line of Credit Facility, Commitment Fee Percentage	0.50%
Greater than or equal to 90 percent [Member]
Interest and Commitment Fee Rates [Line Items]
Margin for base rate loans	2.00%
Margin for eurodollar loans	3.00%
Line of Credit Facility, Commitment Fee Percentage	0.50%

Shareholders' Equity and Stoc45

Shareholders' Equity and Stock Incentive Plans (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Available for Grant	26,275
Ratio of stock based compensation shares to common shares	1.35
Restricted Stock Awards And Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Awards, Compensation Cost Not yet Recognized	$ 31.4
Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years 4 months 24 days
Granted Shares/Units	749,396
Vesting period, in years	3 years
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Awards, Compensation Cost Not yet Recognized	$ 5.9
Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 9 months 18 days
Fair Value of Shares Issued	$ 4.1
Vesting period, in years	2 years
Liability For Cash Stock Appreciation Rights	$ 6.4	$ 11.5
Liability For Cash Stock Appreciation Rights, Classified As Other Accrued Liabilities	6.3	10
Liability For Cash Stock Appreciation Rights Remainder, Classified As Other Long Term Liabilities	$ 0.1	$ 1.5
SARs, Granted	342,440
Expiration period after date of grant, in years	5 years
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Awards, Compensation Cost Not yet Recognized	$ 3.8
Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years 1 month 6 days
Granted Shares/Units	46,787
Fair Value of Shares Issued	$ 1.6
Vesting period, in years	3 years
Maximum [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award Vesting Rights Percentage Range	200.00%
Minimum [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award Vesting Rights Percentage Range	0.00%
Annual Grant of Long-Term Equity Incentive Awards [Member] | Restricted Stock Awards And Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted Shares/Units	695,658
Fair Value of Shares Issued	$ 18.8
Grant of Long-Term Equity Incentive Awards in Lieu of Annual Cash Bonus [Member] | Restricted Stock Awards And Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted Shares/Units	44,465
Fair Value of Shares Issued	$ 1.2

Shareholders' Equity and Stoc46

Shareholders' Equity and Stock Incentive Plans (Summary of Restricted Stock Award and Unit Activity) (Details) - Restricted Stock Awards And Units [Member]	3 Months Ended
	Mar. 31, 2017$ / sharesshares
Restricted Stock Awards and Units [Abstract]
Unvested Shares/Units, Beginning of Period | shares	1,111,710
Granted Shares/Units | shares	749,396
Vested Shares/Units | shares	(569,145)
Forfeited Shares/Units | shares	(3,933)
Unvested Shares/Units, End of Period | shares	1,288,028
Weighted Average Grant Date Fair Value [Abstract]
Grant Date Fair Value, Beginning of Period (USD per share) | $ / shares	$ 36.93
Granted, Grant Date Fair Value (USD per share) | $ / shares	27.07
Vested, Grant Date Fair Value (USD per share) | $ / shares	39.48
Forfeited, Grant Date Fair Value (USD per share) | $ / shares	29.42
Grant Date Fair Value, End of Period (USD per share) | $ / shares	$ 30.09

Shareholders' Equity and Stoc47

Shareholders' Equity and Stock Incentive Plans (Summary of SARs Activity) (Details) - Stock Appreciation Rights (SARs) [Member] $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
SARs, Outstanding, Beginning of period | shares	722,638
SARs, Granted | shares	342,440
SARs, Exercised | shares	(100,000)
SARs, Forfeitures | shares	0
SARs, Outstanding, End of period | shares	965,078
SARs, Exercisable, End of Period | shares	436,739
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Prices, Outstanding, Beginning of Period | $ / shares	$ 23.69
Weighted Average Exercise Prices, Granted | $ / shares	26.94
Weighted Average Exercise Prices, Exercised | $ / shares	17.28
Weighted Average Exercise Prices, Forfeitures | $ / shares	0
Weighted Average Exercise Prices, Outstanding, End of Period | $ / shares	25.51
Weighted Average Exercise Prices, Exercisable, End of Period | $ / shares	$ 23.62
Cash paid at exercises, Stock Appreciation Rights | $	$ 1.3
Weighted Average Remaining Life, Outstanding, End of Period	3 years 4 months 24 days
Weighted Average Remaining Life, Exercisable, End of Period	1 year 9 months 18 days
Aggregate Intrinsic Value, Outstanding, End of Period | $	$ 2.5
Aggregate Intrinsic Value, Exercisable, End of Period | $	$ 2

Shareholders' Equity and Stoc48

Shareholders' Equity and Stock Incentive Plans (Summary of SARs Fair Value Assumptions) (Details) - Stock Appreciation Rights (SARs) [Member]	3 Months Ended
	Mar. 31, 2017$ / sharesRate
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Term	4 years 2 months 26 days
Expected Volatility Rate	54.30%
Risk-free Interest Rate	1.80%
Dividend Yield	0.00%
Weighted Average Grant Date Price | $ / shares	$ 12

Shareholders' Equity and Stoc49

Shareholders' Equity and Stock Incentive Plans (Summary of Performance Share Award Activity) (Details) - Performance Shares [Member]	3 Months Ended
	Mar. 31, 2017$ / sharesshares
Performance Share Awards
Unvested Shares/Units, Beginning of Period	154,510
Granted Shares/Units	46,787
Vested Shares/Units	(56,342)
Forfeited Shares/Units	0
Unvested Shares/Units, End of Period	144,955
Weighted Average Grant Date Fair Value [Abstract]
Grant Date Fair Value, Beginning of Period (USD per share) | $ / shares	$ 58.44
Granted, Grant Date Fair Value (USD per share) | $ / shares	35.14
Vested, Grant Date Fair Value (USD per share) | $ / shares	68.15
Forfeited, Grant Date Fair Value (USD per share) | $ / shares	0
Grant Date Fair Value, End of Period (USD per share) | $ / shares	$ 47.14
Vesting percentage of target performance shares granted	164.00%
Performance shares vested per TSR ranking	(35,858)

Shareholders' Equity and Stoc50

Shareholders' Equity and Stock Incentive Plans (Summary of Performance Share Awards Fair Value Assumptions) (Details) - Performance Shares [Member]	3 Months Ended
	Mar. 31, 2017$ / sharesRate
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of simulations performed	500,000
Expected Term	2 years 11 months 23 days
Expected Volatility Rate	59.20%
Risk-free Interest Rate	1.50%
Dividend Yield	0.00%
Weighted Average Grant Date Price | $ / shares	$ 35.14

Shareholders' Equity and Stoc51

Shareholders' Equity and Stock Incentive Plans (Schedule of Share-Based Compensation Expense) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	$ 2,869	$ 13,442
Less: amounts capitalized	(855)	(1,920)
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost	2,014	11,522
Restricted Stock Awards And Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	5,849	11,594
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	(3,686)	1,232
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	$ 706	$ 616

Derivative Instruments (Narrati

Derivative Instruments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Derivative, Cost of Hedge Net of Cash Received	$ 4.2	$ 4.6
Other Current Liabilities [Member]
Derivative [Line Items]
Derivative, Cost of Hedge Net of Cash Received	2	2
Other Noncurrent Liabilities [Member]
Derivative [Line Items]
Derivative, Cost of Hedge Net of Cash Received	$ 2.2	$ 2.6

Derivative Instruments (Schedul

Derivative Instruments (Schedule of Crude Oil Derivative Positions) (Details) - Crude Oil [Member]	Mar. 31, 2017bbl / d$ / bbls
Swaps [Member] | Q2 2017 [Domain]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	12,000
Weighted Average Floor Price ($/Bbls) | $ / bbls	50.13
Swaps [Member] | Q3 2017 [Domain]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	6,000
Weighted Average Floor Price ($/Bbls) | $ / bbls	54.15
Swaps [Member] | Q4 2017 [Domain]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	3,000
Weighted Average Floor Price ($/Bbls) | $ / bbls	55.01
Energy Related Derivative, Weighted Average Ceiling Price of $60.00 [Member] | FY 2018 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	2,488
Weighted Average Ceiling Price ($/Bbls) | $ / bbls	60
Energy Related Derivative, Weighted Average Ceiling Price of $75.00 [Member] | FY 2018 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	900
Weighted Average Ceiling Price ($/Bbls) | $ / bbls	75
Energy Related Derivative, Weighted Average Ceiling Price of $62.50 [Member] | FY 2019 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	2,975
Weighted Average Ceiling Price ($/Bbls) | $ / bbls	62.50
Energy Related Derivative, Weighted Average Ceiling Price of $77.50 [Member] | FY 2019 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	900
Weighted Average Ceiling Price ($/Bbls) | $ / bbls	77.50
Energy Related Derivative, Weighted Average Ceiling Price of $65.00 [Member] | FY 2020 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	3,675
Weighted Average Ceiling Price ($/Bbls) | $ / bbls	65
Energy Related Derivative, Weighted Average Ceiling Price of $80.00 [Member] | FY 2020 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	900
Weighted Average Ceiling Price ($/Bbls) | $ / bbls	80

Derivative Instruments (Sched54

Derivative Instruments (Schedule of Natural Gas Derivative Positions) (Details) - Natural Gas Derivative Positions [Member]	Mar. 31, 2017MMBTU / d$ / MMBTU
Swaps [Member] | FY 2017
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU / d	20,000
Weighted Average Floor Price ($/MMBtu) | $ / MMBTU	3.30
Call Option [Member] | FY 2017
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU / d	33,000
Weighted Average Ceiling Price ($/MMBtu) | $ / MMBTU	3
Call Option [Member] | FY 2018 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU / d	33,000
Weighted Average Ceiling Price ($/MMBtu) | $ / MMBTU	3.25
Call Option [Member] | FY 2019 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU / d	33,000
Weighted Average Ceiling Price ($/MMBtu) | $ / MMBTU	3.25
Call Option [Member] | FY 2020 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU / d	33,000
Weighted Average Ceiling Price ($/MMBtu) | $ / MMBTU	3.50

Derivative Instruments (Sched55

Derivative Instruments (Schedule of Derivative Instruments in Statement of Financial Position) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Gross amount not offset against collateral, net	$ (25,095)	$ (48,892)
Derivative liabilities (assets), gross amounts offset in the consolidated balance sheets	0	0
Derivative Asset (Liability), Net	(25,095)	(48,892)
Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2,417	6,507
Derivative Asset, Fair Value, Gross Liability	(1,381)	(5,270)
Derivative Asset	1,036	1,237
Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	106	1,313
Derivative Asset, Fair Value, Gross Liability	(106)	(1,313)
Derivative Asset	0	0
Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	(8,837)	(27,871)
Derivative Liability, Fair Value, Gross Asset	1,381	5,270
Derivative Liability	7,456	22,601
Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	(18,781)	(28,841)
Derivative Liability, Fair Value, Gross Asset	106	1,313
Derivative Liability	18,675	27,528
Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	1,036	1,237
Derivative Liability	$ (21,970)	$ (45,552)

Derivative Instruments (Sched56

Derivative Instruments (Schedule of (Gain) Loss on Derivative Instruments) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Derivative Instruments, Gain (Loss), Commodity [Line Items]
(Gain) loss on derivatives, net	$ (25,316)	$ (10,553)
Crude Oil [Member]
Derivative Instruments, Gain (Loss), Commodity [Line Items]
(Gain) loss on derivatives, net	(18,480)	(21,891)
Natural Gas [Member]
Derivative Instruments, Gain (Loss), Commodity [Line Items]
(Gain) loss on derivatives, net	$ (6,836)	$ 11,338

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($)	Mar. 31, 2017	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount	$ 0	$ 0
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	$ 0	$ 0

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis) (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	$ 0	$ 0
Derivative Liability	0	0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	1,036	1,237
Derivative Liability	(21,970)	(45,552)
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0	0
Derivative Liability	$ 0	$ 0

Fair Value Measurements (Sche59

Fair Value Measurements (Schedule of Carrying Value and Estimated Fair Value of Debt Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
7.50% Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	$ 600,000	$ 600,000
7.50% Senior Notes [Member] | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	593,771	593,447
7.50% Senior Notes [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	616,500	624,750
6.25% Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	650,000	650,000
6.25% Senior Notes [Member] | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	640,850	640,546
6.25% Senior Notes [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	650,000	672,750
Other Long Term Debt [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	4,425	4,425
Other Long Term Debt [Member] | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	4,425	4,425
Other Long Term Debt [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt	$ 4,425	$ 4,419

Condensed Consolidating Finan60

Condensed Consolidating Financial Information (Narrative) (Details)	Mar. 31, 2017
Condensed Consolidating Financial Information [Abstract]
Voting interest of the subsidiary owned by the registrant	100.00%

Condensed Consolidating Finan61

Condensed Consolidating Financial Information (Schedule Of Condensed Consolidating Balance Sheet) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Condensed Balance Sheet Statements, Captions [Line Items]
Total current assets	$ 73,226	$ 72,988
Total property and equipment, net	1,634,204	1,545,760
Investment in subsidiaries	0	0
Other assets	7,010	7,579
Total Assets	1,714,440	1,626,327
Current liabilities	228,028	211,959
Long-term liabilities	1,416,485	1,390,910
Total shareholders’ equity	69,927	23,458
Total Liabilities and Shareholders’ Equity	1,714,440	1,626,327
Eliminations [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Total current assets	(2,717,829)	(2,726,355)
Total property and equipment, net	(3,926)	(3,916)
Investment in subsidiaries	1,223,475	1,282,292
Other assets	0	0
Total Assets	(1,498,280)	(1,447,979)
Current liabilities	(2,720,849)	(2,729,375)
Long-term liabilities	15,878	15,878
Total shareholders’ equity	1,206,691	1,265,518
Total Liabilities and Shareholders’ Equity	(1,498,280)	(1,447,979)
Parent Company [Member] | Reportable Legal Entities [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Total current assets	2,724,856	2,735,830
Total property and equipment, net	41,196	42,181
Investment in subsidiaries	(1,223,475)	(1,282,292)
Other assets	6,855	7,423
Total Assets	1,549,432	1,503,142
Current liabilities	90,083	114,805
Long-term liabilities	1,372,638	1,348,105
Total shareholders’ equity	86,711	40,232
Total Liabilities and Shareholders’ Equity	1,549,432	1,503,142
Combined Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Total current assets	66,199	63,513
Total property and equipment, net	1,593,134	1,503,695
Investment in subsidiaries	0	0
Other assets	155	156
Total Assets	1,659,488	1,567,364
Current liabilities	2,854,994	2,822,729
Long-term liabilities	27,969	26,927
Total shareholders’ equity	(1,223,475)	(1,282,292)
Total Liabilities and Shareholders’ Equity	1,659,488	1,567,364
Combined Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Total current assets	0	0
Total property and equipment, net	3,800	3,800
Investment in subsidiaries	0	0
Other assets	0	0
Total Assets	3,800	3,800
Current liabilities	3,800	3,800
Long-term liabilities	0	0
Total shareholders’ equity	0	0
Total Liabilities and Shareholders’ Equity	$ 3,800	$ 3,800

Condensed Consolidating Finan62

Condensed Consolidating Financial Information (Schedule Of Condensed Consolidating Statement Of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Condensed Income Statements, Captions [Line Items]
Total revenues	$ 151,355	$ 81,262
Total costs and expenses	111,334	392,536
Income (loss) before income taxes	40,021	(311,274)
Income tax (expense) benefit	0	(121)
Equity (deficit) in income of subsidiaries	0	0
Net Income (loss)	40,021	(311,395)
Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Total revenues	0	0
Total costs and expenses	10	376
Income (loss) before income taxes	(10)	(376)
Income tax (expense) benefit	0	(121)
Equity (deficit) in income of subsidiaries	(58,817)	281,101
Net Income (loss)	(58,827)	280,604
Parent Company [Member] | Reportable Legal Entities [Member]
Condensed Income Statements, Captions [Line Items]
Total revenues	82	115
Total costs and expenses	18,868	29,912
Income (loss) before income taxes	(18,786)	(29,797)
Income tax (expense) benefit	0	0
Equity (deficit) in income of subsidiaries	58,817	(281,101)
Net Income (loss)	40,031	(310,898)
Combined Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Income Statements, Captions [Line Items]
Total revenues	151,273	81,147
Total costs and expenses	92,456	362,248
Income (loss) before income taxes	58,817	(281,101)
Income tax (expense) benefit	0	0
Equity (deficit) in income of subsidiaries	0	0
Net Income (loss)	58,817	(281,101)
Combined Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Income Statements, Captions [Line Items]
Total revenues	0	0
Total costs and expenses	0	0
Income (loss) before income taxes	0	0
Income tax (expense) benefit	0	0
Equity (deficit) in income of subsidiaries	0	0
Net Income (loss)	$ 0	$ 0

Condensed Consolidating Finan63

Condensed Consolidating Financial Information (Schedule Of Condensed Consolidating Statement Of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 76,408	$ 53,868
Net cash provided by (used in) investing activities	(113,826)	(124,821)
Net cash provided by (used in) financing activities	35,615	30,193
Net Decrease in Cash and Cash Equivalents	(1,803)	(40,760)
Cash and Cash Equivalents, Beginning of Period	4,194	42,918
Cash and Cash Equivalents, End of Period	2,391	2,158
Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	0
Net cash provided by (used in) investing activities	(9,493)	67,565
Net cash provided by (used in) financing activities	9,493	(67,565)
Net Decrease in Cash and Cash Equivalents	0	0
Cash and Cash Equivalents, Beginning of Period	0	0
Cash and Cash Equivalents, End of Period	0	0
Parent Company [Member] | Reportable Legal Entities [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(47,297)	(2,156)
Net cash provided by (used in) investing activities	9,879	(68,797)
Net cash provided by (used in) financing activities	35,615	30,193
Net Decrease in Cash and Cash Equivalents	(1,803)	(40,760)
Cash and Cash Equivalents, Beginning of Period	4,194	42,918
Cash and Cash Equivalents, End of Period	2,391	2,158
Combined Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	123,705	56,024
Net cash provided by (used in) investing activities	(114,212)	(122,849)
Net cash provided by (used in) financing activities	(9,493)	66,825
Net Decrease in Cash and Cash Equivalents	0	0
Cash and Cash Equivalents, Beginning of Period	0	0
Cash and Cash Equivalents, End of Period	0	0
Combined Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	0
Net cash provided by (used in) investing activities	0	(740)
Net cash provided by (used in) financing activities	0	740
Net Decrease in Cash and Cash Equivalents	0	0
Cash and Cash Equivalents, Beginning of Period	0	0
Cash and Cash Equivalents, End of Period	$ 0	$ 0

Supplemental Cash Flow Inform64

Supplemental Cash Flow Information (Schedule of Cash Flow Supplemental Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Interest Paid, Net	$ 19,480	$ 17,553
Income Taxes Paid	0	0
Change in capital expenditure payables and accruals	28,139	(27,989)
Stock-based compensation expense capitalized to oil and gas properties	855	1,920
Asset retirements obligations capitalized to oil and gas properties	447	518
Other Non-Cash Investing Activities	$ 343	$ 1,485

Subsequent Events (Narrative) (

Subsequent Events (Narrative) (Details) $ in Thousands	1 Months Ended		3 Months Ended		12 Months Ended
	May 31, 2017	Apr. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2016USD ($)	May 04, 2017USD ($)
Subsequent Event [Line Items]
Derivative, Cost of Hedge Net of Cash Received			$ 4,200			$ 4,600
Payments to acquire oil and gas property			$ 7,032	$ 0
Subsequent Event [Member]
Subsequent Event [Line Items]
Derivative, Cost of Hedge Net of Cash Received					$ 2,800
Payments to acquire oil and gas property		$ 9,800
7.50% Senior Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			7.50%
Senior Secured Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 1,000,000
Line of Credit Facility, Current Borrowing Capacity			$ 600,000
Line of Credit Facility, Commitment Fee Percentage			0.50%
Senior Secured Revolving Credit Facility [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity							$ 2,000,000
Line of Credit Facility, Current Borrowing Capacity							900,000
Line of Credit Facility, Elected Borrowing Capacity							800,000
Line of Credit Facility, Commitment Fee Percentage	0.375%
Utilization of lender commitments	50.00%
Consolidated Cash Balance Threshold							$ 50,000
Credit Facility Availability Threshold							20.00%
Senior Secured Revolving Credit Facility [Member] | Maximum [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Ratio of total debt to EBITDA	4
Adjusted ratio of total debt to EBITDA							3.50

Subsequent Events, Derivative I

Subsequent Events, Derivative Instruments (Schedule of Crude Oil Derivative Positions) (Details) - Crude Oil [Member]	Apr. 10, 2017bbl / d$ / bbls	Apr. 07, 2017bbl / d$ / bbls	Mar. 31, 2017bbl / d$ / bbls
Swaps [Member] | Q3 2017 [Domain]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d			6,000
Weighted Average Floor Price ($/Bbls)			54.15
Swaps [Member] | Q4 2017 [Domain]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d			3,000
Weighted Average Floor Price ($/Bbls)			55.01
Subsequent Event [Member] | Swaps [Member] | Q3 2017 [Domain]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d		6,000
Weighted Average Floor Price ($/Bbls)		53.28
Subsequent Event [Member] | Swaps [Member] | Q4 2017 [Domain]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d		6,000
Weighted Average Floor Price ($/Bbls)		53.28
Subsequent Event [Member] | Three-way Collars [Member] | FY 2018 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | bbl / d	6,000
Weighted Average Sub-Floor Price ($/Bbls)	40
Weighted Average Floor Price ($/Bbls)	50
Weighted Average Ceiling Price ($/Bbls)	65