MNRL Sub (MNRL) 10-Q 20 May 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	May 10, 2019
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Trading Symbol	MNRL
Entity Registrant Name	Brigham Minerals, Inc.
Entity Central Index Key	0001745797
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Common Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		21,997,198
Common Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		28,777,802

Condensed Balance Sheet

Condensed Balance Sheet - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 0	$ 0
Non-current assets:
Investment in unconsolidated affiliates	63,081	62,388
Total assets	63,081	62,388
Current liabilities:
Current income tax payable	165	128
Total current liabilities	165	128
Deferred income taxes	3,598	3,476
Shareholders' equity:
Shareholders' contributed capital	34,491	34,491
Additional paid-in capital	(3,057)	(3,057)
Accumulated earnings	27,884	27,350
Stockholders' Equity Attributable to Parent	59,318	58,784
Total liabilities and shareholders' equity	63,081	62,388
Brigham Resources, LLC
Current assets:
Cash and cash equivalents	8,564	31,985
Restricted cash	1,199	474
Accounts receivable	19,608	20,695
Prepaid expenses and other	8,658	7,103
Short-term derivative assets	146	1,057
Total current assets	38,175	61,314
Non-current assets:
Unevaluated property	234,265	228,151
Evaluated property	325,068	289,851
Less accumulated depreciation, depletion and amortization	(32,598)	(27,628)
Total oil and gas properties, net	526,735	490,374
Other property and equipment	5,458	5,408
Less accumulated depreciation	(3,261)	(3,115)
Other property and equipment—net	2,197	2,293
Other assets, net	45	45
Total assets	567,152	554,026
Current liabilities:
Accounts payable and accrued liabilities	4,256	5,534
Current portion of debt	4,596	2,188
Total current liabilities	8,852	7,722
Long-term debt	176,298	168,517
Other non-current liabilities	255	235
Shareholders' equity:
Shareholders' contributed capital	208,728	208,728
Accumulated earnings	173,019	168,824
Total members’ equity	381,747	377,552
Total liabilities and shareholders' equity	$ 567,152	$ 554,026

Condensed Statement of Operatio

Condensed Statement of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating Expenses:
Income from equity method investment	$ 693	$ 1,354
Income tax expense	159	0
Net Income	534	1,354
Pro Forma Information (Unaudited)
Unaudited supplemental pro forma tax expense (See Note 1 - Organization and Basis of Presentation)	0	311
Unaudited supplemental pro forma net income	0	1,043
Brigham Resources, LLC
Revenues:
Mineral and royalty revenues	17,590	11,864
Lease bonus and other revenues	675	2,219
Total revenues	18,265	14,083
Operating Expenses:
Gathering, transportation and marketing	1,114	1,095
Severance and ad valorem taxes	1,379	760
Depreciation, depletion and amortization	5,116	2,545
General and administrative	1,949	1,464
Total operating expenses	9,558	5,864
Income from operations	8,707	8,219
Loss on derivative instruments, net	(685)	(359)
Interest expense, net	(3,825)	(474)
Gain on sale and distribution of equity securities	0	823
Other income, net	29	3
Income before income taxes	4,226	8,212
Income tax expense	31	16
Net Income	$ 4,195	$ 8,196

Condensed Statement of Comprehe

Condensed Statement of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net income	$ 534	$ 1,354
Other comprehensive income
Unrealized gains (losses) on available for sale equity securities, net	0	23
Reclassification of (gains)/losses on sale and distribution of available for sale equity securities	0	(136)
Other comprehensive income	0	(113)
Other comprehensive income		(113)
Comprehensive income	534	1,241
Brigham Resources, LLC
Net income	4,195	8,196
Other comprehensive income
Unrealized gains (losses) on available for sale equity securities, net	0	141
Reclassification of (gains)/losses on sale and distribution of available for sale equity securities	0	(823)
Other comprehensive income	0	(682)
Comprehensive income	$ 4,195	$ 7,514

Condensed Statement of Changes

Condensed Statement of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Shareholders’ Contributed Capital	Additional Paid-in Capital	Accumulated Earnings	Accumulated Other Comprehensive Income	Brigham Resources, LLC	Brigham Resources, LLCShareholders’ Contributed Capital	Brigham Resources, LLCAccumulated Earnings	Brigham Resources, LLCAccumulated Other Comprehensive Income
Beginning balance at Dec. 31, 2017	$ 49,933	$ 27,436	$ 0	$ 22,384	$ 113
Beginning balance at Dec. 31, 2017						$ 302,174	$ 166,030	$ 135,462	$ 682
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contributions	3,573	3,573	0			21,625	21,625
Distributions	(702)	(702)				(4,246)	(4,246)
Other comprehensive income	(113)				(113)	(682)			(682)
Net income	1,354			1,354		8,196		8,196
Ending balance at Mar. 31, 2018	54,045	30,307	0	23,738	0
Beginning balance at Mar. 31, 2018						327,067	183,409	143,658	$ 0
Beginning balance at Dec. 31, 2018	58,784	34,491	(3,057)	27,350	0
Beginning balance at Dec. 31, 2018					0	377,552	208,728	168,824
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income						0
Net income	534			534		4,195		4,195
Ending balance at Mar. 31, 2019	$ 59,318	$ 34,491	$ (3,057)	$ 27,884	0
Beginning balance at Mar. 31, 2019					$ 0	$ 381,747	$ 208,728	$ 173,019

Condensed Statement of Cash Flo

Condensed Statement of Cash Flows - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net income		$ 534	$ 1,354
Adjustments to reconcile net income to net cash provided by operating activities:
(Income) from equity method investment		(693)	(1,354)
Deferred income taxes		122	0
Changes in operating assets and liabilities:
Increase in current income taxes payable		37	0
Net cash provided by operating activities		0	0
Cash flows from investing activities
Returns of investment in equity method investee		0	0
Contributions to equity method investee		0	0
Net cash (used in) provided by investing activities		0	0
Cash flows from financing activities
Proceeds from shareholders' investment		0	0
Distributions		0	0
Net cash provided by (used in) financing activities		0	0
Increase (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 disclosure of non cash activity:
Deemed contributions	[1]	0	3,573
Deemed distributions	[1]	0	(702)
Other comprehensive income		0	(113)
Brigham Resources, LLC
Cash flows from operating activities
Net income		4,195	8,196
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization		5,116	2,545
Amortization of debt issue costs		190	37
Deferred income taxes		18	18
Loss on derivative instruments, net		685	359
Net cash received/(paid) for derivative settlements		198	(118)
(Gain) loss on sale of equity securities		0	(823)
Changes in operating assets and liabilities:
Decrease/(increase) in accounts receivable		1,115	(1,610)
(Increase) in other current assets		(1,555)	(283)
(Increase) in other deferred charges		0	(32)
Increase/(decrease) in accounts payable and accrued liabilities		77	(1,681)
Net cash provided by operating activities		10,039	6,608
Cash flows from investing activities
Acquisitions of oil and gas properties		(42,686)	(25,624)
Additions to other fixed assets		(48)	(129)
Proceeds from sale of oil and gas properties, net		0	125
Changes in restricted cash held in escrow for acquisitions		(726)	0
Net cash (used in) provided by investing activities		(43,460)	(25,628)
Cash flows from financing activities
Borrowings of long-term debt		10,000	13,000
Capital contributions		0	21,624
Net cash provided by (used in) financing activities		10,000	34,624
Cash and cash equivalents, beginning of period		31,985
Cash and cash equivalents, end of period		8,564
(Decrease)/increase in cash and cash equivalents		(23,421)	15,604
Cash and cash equivalents, beginning of period		31,985	6,886
Cash and cash equivalents, end of period		8,564	22,490
Supplemental disclosure of non cash activity:
Accrued capital expenditures		72	43
Equity securities distributed		0	4,246
Supplemental cash flow information:
Cash interest payments		$ 3,543	$ 458
[1]	Represents Brigham Minerals’ portion of the members’ contributions to Brigham Resources and Brigham Resources’ distributions to its members. As such, they are non-cash, deemed contributions and distributions.

Busines and Basis of Presentati

Busines and Basis of Presentation	3 Months Ended
	Mar. 31, 2019
Schedule of Equity Method Investments [Line Items]
Business and Basis of Presentation	Organization and Basis of Presentation Brigham Minerals, Inc. (“Brigham Minerals”) is a Delaware corporation formed in June 2018 to become a holding company. Brigham Minerals acquired an indirect interest in Brigham Resources, LLC (“Brigham Resources”) on July 16, 2018 in a series of restructuring transactions pursuant to which certain entities affiliated with Warburg Pincus LLC (“Warburg Pincus”) contributed all of their respective interests in the entities through which they held interests in Brigham Resources to Brigham Minerals in exchange for all of the outstanding shares of common stock of Brigham Minerals (the "July 2018 restructuring"). As a result of such restructuring transactions, Brigham Minerals became wholly owned by an entity affiliated with Warburg Pincus, and Brigham Minerals indirectly owned a 16.5% membership interest in Brigham Resources. The remaining outstanding membership interests of Brigham Resources remained with certain other entities affiliated with Warburg Pincus, Yorktown Partners LLC and Pine Brook Road Advisors, LP, our management and our other investors (collectively, the "Existing Owners"). On November 20, 2018, Brigham Resources underwent a second series of restructuring transactions (the “November 2018 restructuring”). In the November 2018 restructuring, Brigham Resources became a wholly owned subsidiary of Brigham Minerals Holdings, LLC (“Brigham LLC”), which is a wholly owned subsidiary of Brigham Equity Holdings, LLC (“Brigham Equity Holdings”), and Brigham Equity Holdings became wholly owned by the owners of Brigham Resources immediately prior to such restructuring, directly or indirectly through Brigham Minerals. As a result of the foregoing transactions, there was no change in the control or economic interests of the Existing Owners and Brigham Minerals in Brigham Resources, although their ownership became indirect through Brigham Equity Holdings and its wholly owned subsidiary, Brigham LLC. The July 2018 restructuring and the November 2018 restructuring are collectively referred to herein as, the "corporate reorganization." Brigham Resources wholly owns Brigham Minerals, LLC and Rearden Minerals, LLC (collectively, the “Minerals Subsidiaries”), which are Brigham Resources’ sole material assets, and also owns Brigham Resources Operating, LLC (“Brigham Operating”), an upstream oil and gas exploration and production business in the southern Delaware Basin of West Texas. In February 2017, Brigham Operating completed the sale of substantially all of its oil and natural gas properties to an unrelated third-party purchaser, following which Brigham Operating’s only material assets consisted of an ownership interest in Oryx Southern Delaware Holdings, LLC (“Oryx”), an entity that operates a crude oil gathering system located in the southern Delaware Basin. Immediately prior to Brigham Minerals' initial public offering of shares of its Class A common stock, which was completed in April 2019 (the "IPO" or the "Offering"), Brigham Resources distributed to its members or their affiliates 100% of the equity interests in Brigham Operating. See "Note 7 - Subsequent Events" below. Subsequent to the distribution, Brigham Resources no longer had any direct or indirect ownership interest in Brigham Operating. Accordingly, the financial statements of Brigham Minerals reflect its 16.5% membership interest in Brigham Resources, excluding the assets, liabilities and results of operations of Brigham Operating, which we refer to herein as our “predecessor.” Brigham Minerals uses the equity method of accounting for its investment in Brigham Resources because its 16.5% ownership in Brigham Resources provides Brigham Minerals with significant influence, but not with a controlling financial interest or the ability to direct the most significant activities of, Brigham Minerals. The accompanying unaudited interim financial statements of Brigham Minerals have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”), except that, in accordance with the instructions to Form 10-Q, they do not include all of the notes required for financial statements prepared in conformity with U.S. GAAP. Accordingly, the accompanying unaudited interim financial statements should be read in conjunction with our audited financial statements included in the registration statement on Form S-1, as amended, filed with the Securities and Exchange Commission (“SEC”) and declared effective on April 17, 2019 (the "IPO registration statement"). The unaudited interim financial statements reflect all normal recurring adjustments that, in the opinion of management, are necessary for a fair representation. The results of operations for the three months ended March 31, 2019 are not necessarily indicative of the results to be expected for the full year. Brigham Minerals operates in one segment: oil and natural gas exploration and production. Transfers of a business between entities under common control are accounted for as if the transfer occurred at the beginning of the period, and prior years are retrospectively adjusted to furnish comparative information. The July 2018 restructuring has been accounted for as transactions between entities under common control; thus the accompanying financial statements and related notes of Brigham Minerals have been retrospectively recast to include the historical results and operations of Brigham Resources at historical carrying values as if Brigham Minerals had held its ownership interest in Brigham Resources for all periods presented. The statement of operations includes unaudited supplemental pro forma information. The unaudited supplemental pro forma information gives effect to an adjustment to include a provision for income taxes as if Brigham Minerals was a taxable corporation as of January 1, 2018, computing pro forma entity level income tax expense using the estimated effective rate in effect, inclusive of all applicable U.S. federal, state and local income taxes.
Brigham Resources, LLC
Schedule of Equity Method Investments [Line Items]
Business and Basis of Presentation	Business and Basis of Presentation Description of the Business Brigham Resources, LLC (“Brigham Resources”), a Delaware limited liability company, was formed on March 28, 2013 as a holding company with no independent operations apart from its ownership of the subsidiaries described herein. Brigham Minerals, LLC and Rearden Minerals, LLC (collectively, “Minerals Subsidiaries”), Delaware limited liability companies, were formed on October 17 and December 21, 2012, respectively, to pursue the acquisition of oil and natural gas mineral and royalty interests in liquids-rich resource plays in the continental United States (the “Minerals Business”). The Mineral Subsidiaries own producing and nonproducing mineral and royalty interests in 38 counties in Colorado, New Mexico, North Dakota, Oklahoma, Texas and Wyoming. Concurrent with the formation of Brigham Resources, on April 5, 2013, Brigham Resources purchased 100% of the common units of the Mineral Subsidiaries. Brigham Resources Management, LLC (“Brigham Management, LLC”), a Delaware limited liability company formed on March 28, 2013, provides administrative services to Brigham Resources and the Minerals Subsidiaries. References to “we,” “us” and “our” mean Brigham Resources. Brigham Minerals, Inc. (“Brigham Minerals”) is a Delaware corporation formed in June 2018 to become a holding company. Brigham Minerals acquired an indirect interest in Brigham Resources on July 16, 2018 in a series of restructuring transactions pursuant to which certain entities affiliated with Warburg Pincus LLC (“Warburg Pincus”) contributed all of their respective interests in the entities through which they held interests in Brigham Resources to Brigham Minerals in exchange for all of the outstanding shares of common stock of Brigham Minerals. As a result of such restructuring transactions, Brigham Minerals became wholly owned by certain entities affiliated with Warburg Pincus, and Brigham Minerals directly owned a 16.5% membership interest in Brigham Resources. The remaining outstanding membership interests of Brigham Resources remained with its other existing owners. Basis of Presentation The accompanying condensed consolidated financial statements of Brigham Resources are comprised of the financial statements of the Minerals Subsidiaries and Brigham Management, LLC and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”), except that, in accordance with the instructions to Form 10-Q, they do not include all of the notes required for financial statements prepared in conformity with U.S. GAAP. Accordingly, the accompanying unaudited condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements included in the registration statement on Form S-1, as amended, filed with the Securities and Exchange Commission (“SEC”) and declared effective on April 17, 2019 (the "IPO registration statement"). The financial statements included herein reflect all normal recurring adjustments that, in the opinion of management, are necessary for a fair presentation. All intercompany balances and transactions have been eliminated.The results of operations for the three months ended March 31, 2019 are not necessarily indicative of the results to be expected for the full year. Brigham Resources operates in one segment: oil and natural gas exploration and production. Historically, Brigham Resources has owned and operated two distinct lines of business through its subsidiaries: • the Minerals Business through the Minerals Subsidiaries; and • an upstream oil and gas exploration and production business (the “Upstream Business”) in the Southern Delaware Basin of West Texas (including interests in certain related gathering systems) through Brigham Resources Operating, LLC (“Brigham Operating”). In April of 2019, Brigham Minerals completed the initial public offering of shares of its Class A common stock (the “Offering”). In connection with the Offering, Brigham Minerals, Brigham Resources and certain other affiliated entities entered into a series of reorganization transactions pursuant to which 100% of the equity interests in Brigham Operating were distributed to the ultimate equity owners of Brigham Resources. See “Note 10 - Subsequent Events” below. Subsequent to such distribution, Brigham Resources no longer had any direct or indirect ownership interest in Brigham Operating. Accordingly, the accompanying condensed consolidated financial statements of Brigham Resources exclude the assets, liabilities and results of operations of Brigham Operating.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Emerging Growth Company Status As a company with less than $1.07 billion in revenues during its last fiscal year, Brigham Minerals qualifies as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). An emerging growth company may take advantage of specified reduced reporting and other regulatory requirements. Brigham Minerals will remain an “emerging growth company” until as late as the last day of Brigham Minerals’ 2023 fiscal year, or until the earliest of (i) the last day of the fiscal year in which Brigham Minerals has $1.07 billion or more in annual revenues; (ii) the date on which Brigham Minerals becomes a “large accelerated filer” (the fiscal year-end on which the total market value of Brigham Minerals’ common equity securities held by non-affiliates is $700 million or more as of June 30); (iii) the date on which Brigham Minerals issues more than $1.0 billion of non-convertible debt over a three-year period. As a result of Brigham Minerals’ election to avail itself of certain provisions of the JOBS Act, the information that Brigham Minerals provides may be different than the information provided by other public companies. Recently Issued Accounting Standards In January 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2017-01, Clarifying the Definition of a Business. This guidance assists in determining whether a transaction should be accounted for as an acquisition or disposal of assets or as a business. This ASU provides a screen that when substantially all of the fair value of the gross assets acquired, or disposed of, are concentrated in a single identifiable asset, or a group of similar identifiable assets, the set will not be considered a business. If the screen is not met, a set must include an input and a substantive process that together significantly contribute to the ability to create an output to be considered a business. The new standard becomes effective for us during the fiscal year ending December 31, 2019 and interim periods within the fiscal year ending December 31, 2020 and is required to be adopted using a prospective approach. Although early application is permitted, we have not adopted ASU 2017-01 early. The implementation of the new standard is not anticipated to have a material impact on the condensed consolidated financial statements. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows, which amends ASC 230 to add or clarify guidance on the classification and presentation of restricted cash in the statement of cash flows. The ASU requires entities to show the changes in the total of cash, cash equivalents, restricted cash and restricted cash equivalents in the statement of cash flows. As a result, entities will no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statement of cash flows. The new standard becomes effective for us during the fiscal year ended December 31, 2019 and interim periods within the fiscal year ending December 31, 2020 and is required to be adopted utilizing retrospective application. Although early application is permitted, we have not adopted ASU 2016-18 early. In February 2016, the FASB issued ASU 2016-02, Leases, which requires all leasing arrangements to be presented in the balance sheet as liabilities along with a corresponding asset. ASU 2016-02 does not apply to leases of mineral rights to explore for or use crude oil and natural gas. The ASU will replace most existing lease guidance in GAAP when it becomes effective. In January 2018, the FASB issued ASU 2018-01, Land Easement Practical Expedient for Transition to Topic 842, to provide an optional practical expedient to not evaluate existing or expired land easements that were not previously accounted for as leases under Topic 840. In July 2018, the FASB issued ASU 2018-11 Leases (Topic 842): Targeted Improvements, which provides for another transition method, in addition to the existing transition method, by allowing entities to initially apply the new leases standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption (i.e. comparative periods presented in the financial statements will continue to be in accordance with current GAAP (Topic 840, Leases)). The new standard becomes effective for us during the fiscal year ending December 31, 2020 and interim periods within the fiscal year ending December 31, 2021 and early adoption is permitted. We are currently evaluating the impact, if any, that the adoption of this update will have on our consolidated financial statements and related disclosures. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. This ASU supersedes the revenue recognition requirements in Topic 605, Revenue Recognition, and industry-specific guidance in Subtopic 932-605, Extractive Activities-Oil and Gas-Revenue Recognition, and requires an entity to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration the entity expects to be entitled to in exchange for those goods or services. Consistent with our status as an emerging growth company, ASU 2014-09 becomes effective for us for the fiscal year ending on December 31, 2019 and interim periods within the fiscal year ending December 31, 2020. We intend to adopt the standard using the modified retrospective approach. We completed our review of revenue contracts covering our material revenue streams, designed to evaluate any potential changes in revenue recognition upon adoption of the new standard, and concluded that the implementation of the new standard will not have a material impact on the consolidated financial statements. We also evaluated the information technology and internal control changes that may be required to implement the new standard based on the results of our contract review process. Investment in equity method investee Brigham Minerals accounts for its 16.5% investment in Brigham Resources using the equity method. Under the equity method, carrying value is adjusted for Brigham Minerals’ share of the investee’s earnings and losses, as well as capital contributions and distributions from the investee. Distributions in excess of equity method earnings are recognized as a return of investment and recorded as investing cash inflows in the accompanying statements of cash flows. Use of estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities in the financial statements and accompanying notes. Although management believes these estimates are reasonable, actual results could differ from these estimates. Changes in estimates are recorded prospectively. Income Taxes The Company accounts for income taxes using the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are calculated by applying existing tax laws and the rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. Brigham Resources, the Company’s predecessor, is a limited liability company that is not subject to U.S. federal income tax. As part of the July 2018 restructuring, certain entities affiliated with Warburg Pincus contributed all of their respective interests in certain wholly owned “blocker” entities through which they held interests in Brigham Resources to Brigham Minerals in exchange for all of the outstanding shares of common stock of Brigham Minerals. On the date of the July 2018 restructuring, a corresponding “first day” tax charge of approximately $3.1 million was recorded to establish a net deferred tax liability for differences between the tax and book basis of the investment in Brigham Resources. The offset of the deferred tax liability was recorded to additional paid-in-capital. Brigham Minerals is a corporation and it is subject to U.S. federal income tax. The tax implications of the July 2018 restructuring and the tax impact of Brigham Minerals’ status as a taxable corporation subject to U.S. federal income tax have been reflected in the accompanying financial statements. The effective combined U.S. federal and state income tax rate for the three months ended March 31, 2019 was 23.0% percent. Total income tax expense differed from the U.S. federal statutory tax rates due to state taxes. The components of the income tax provision were as follows for the periods indicated: Three Months Ended March 31, 2019 2018 (In thousands) Federal Current $ 33 $ — Deferred 112 — Total federal expense 145 — State Current 3 — Deferred 11 — Total state expense 14 — Total income tax provision $ 159 $ — No income tax expense was recognized for the periods prior to the July 2018 restructuring. The following table reconciles the income tax provision with income tax expense at the federal statutory rate for the periods indicated: Three Months Ended March 31, 2019 2018 (In thousands) Income (Loss) before income taxes $ 693 $ — Income tax at the federal statutory rate 146 — State income taxes, net of federal benefit 18 — Percentage depletion in excess of basis (5 ) Total income tax provision $ 159 $ — The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities were as follows: March 31, 2019 December 31, 2018 (In thousands) Noncurrent: Deferred tax assets: $ — $ — Total noncurrent deferred tax assets — — Deferred tax liabilities: Investment in subsidiary 3,598 3,476 Total noncurrent deferred tax liabilities 3,598 3,476 Net noncurrent deferred tax liability $ 3,598 $ 3,476 Impairment of equity method investee Brigham Minerals reviews its investment in Brigham Resources for other-than-temporary impairment whenever events or changes in circumstances indicate that the carrying amount of the investment might not be recoverable. Brigham Minerals would recognize any loss other than a temporary decline in value. For the three months ended March 31, 2019 and 2018 , no impairment loss was recorded.
Brigham Resources, LLC
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Significant Accounting Policies Significant accounting policies are disclosed in Brigham Resources' audited consolidated financial statements and notes for the year ended December 31, 2018 , presented in the IPO registration statement. There have been no changes in such policies or the application of such policies during the three months ended March 31, 2019 . Recently Issued Accounting Standards Brigham Minerals’ status as an emerging growth company under Section 107 of the JOBS Act permits it to delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. Brigham Minerals is choosing to take advantage of this extended transition period and, as a result, Brigham Minerals and Brigham Resources will comply with new or revised accounting standards on the relevant dates on which adoption of such standards is required for private companies. In January 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2017-01, Clarifying the Definition of a Business. This guidance assists in determining whether a transaction should be accounted for as an acquisition or disposal of assets or as a business. This ASU provides a screen that when substantially all of the fair value of the gross assets acquired, or disposed of, are concentrated in a single identifiable asset, or a group of similar identifiable assets, the set will not be considered a business. If the screen is not met, a set must include an input and a substantive process that together significantly contribute to the ability to create an output to be considered a business. The new standard becomes effective for us during the fiscal year ending December 31, 2019 and interim periods within the fiscal year ending December 31, 2020 and is required to be adopted using a prospective approach. Although early application is permitted, we have not adopted ASU 2017-01 early. The implementation of the new standard is not anticipated to have a material impact on the condensed consolidated financial statements. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows, which amends ASC 230 to add or clarify guidance on the classification and presentation of restricted cash in the statement of cash flows. The ASU requires entities to show the changes in the total of cash, cash equivalents, restricted cash and restricted cash equivalents in the statement of cash flows. As a result, entities will no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statement of cash flows. The new standard becomes effective for us during the fiscal year ended December 31, 2019 and interim periods within the fiscal year ending December 31, 2020 and is required to be adopted utilizing retrospective application. Although early application is permitted, we have not adopted ASU 2016-18 early. In February 2016, the FASB issued ASU 2016-02, Leases, which requires all leasing arrangements to be presented in the balance sheet as liabilities along with a corresponding asset. ASU 2016-02 does not apply to leases of mineral rights to explore for or use crude oil and natural gas. The ASU will replace most existing lease guidance in GAAP when it becomes effective. In January 2018, the FASB issued ASU 2018-01, Land Easement Practical Expedient for Transition to Topic 842, to provide an optional practical expedient to not evaluate existing or expired land easements that were not previously accounted for as leases under Topic 840. In July 2018, the FASB issued ASU 2018-11 Leases (Topic 842): Targeted Improvements, which provides for another transition method, in addition to the existing transition method, by allowing entities to initially apply the new leases standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption (i.e. comparative periods presented in the financial statements will continue to be in accordance with current GAAP (Topic 840, Leases)). The new standard becomes effective for us during the fiscal year ending December 31, 2020 and interim periods within the fiscal year ending December 31, 2021 and early adoption is permitted. We are currently evaluating the impact, if any, that the adoption of this update will have on our consolidated financial statements and related disclosures. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. This ASU supersedes the revenue recognition requirements in Topic 605, Revenue Recognition, and industry-specific guidance in Subtopic 932-605, Extractive Activities-Oil and Gas-Revenue Recognition, and requires an entity to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration the entity expects to be entitled to in exchange for those goods or services. Consistent with our status as an emerging growth company, ASU 2014-09 becomes effective for us for the fiscal year ending on December 31, 2019 and interim periods within the fiscal year ending December 31, 2020. We intend to adopt the standard using the modified retrospective approach. We completed our review of revenue contracts covering our material revenue streams, designed to evaluate any potential changes in revenue recognition upon adoption of the new standard, and concluded that the implementation of the new standard will not have a material impact on the consolidated financial statements. We also evaluated the information technology and internal control changes that may be required to implement the new standard based on the results of our contract review process.

Equity method investment

Equity method investment	3 Months Ended
	Mar. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Equity method investment	Equity method investment Brigham Minerals obtained its 16.5% interest in Brigham Resources as part of the July 2018 restructuring. Due to our significant influence over the operations of Brigham Resources, we account for this interest utilizing the equity method. Any income or losses are recorded in the statement of operations while contributions increase the value of the investment and distributions decrease the value of the investment. There is no difference in the basis of the investment and the underlying equity of Brigham Resources. The condensed consolidated financial statements of Brigham Resources are included elsewhere in this Quarterly Report. Below is a roll forward of the investment balance for the three months ended March 31, 2019 and 2018 (in thousands). All deemed contributions and distributions are non-cash. Balance-December 31, 2018 $ 62,388 Income from equity method investment 693 Balance-March 31, 2019 $ 63,081 Balance-December 31, 2017 $ 49,933 Income from equity method investment 1,354 Deemed contributions from equity method investee 3,573 Deemed distributions (702 ) Other comprehensive income (113 ) Balance-March 31, 2018 $ 54,045 As discussed under "Note 7 - Subsequent Events" below, Brigham Minerals completed certain additional reorganization transactions in connection with the consummation of the Offering. As a result of such transactions, Brigham Minerals will no longer utilize the equity method for its investment in Brigham Resources for future periods. As such, Brigham Minerals will consolidate the results of its controlling interest in its investment with a non-controlling interest for the portion of Brigham Resources not owned by Brigham Minerals.

Oil and Gas Properties

Oil and Gas Properties	3 Months Ended
	Mar. 31, 2019
Brigham Resources, LLC
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Oil and Gas Properties	Oil and Gas Properties Brigham Resources uses the full cost method of accounting for its oil and natural gas properties. Under this method, all acquisition costs incurred for the purpose of acquiring mineral and royalty interests, including certain internal costs, are capitalized into a full cost pool. Costs associated with general corporate activities are expensed in the period incurred. Oil and gas properties consisted of the following: March 31, December 31, (In thousands) Oil and gas properties, at cost, using the full cost method of accounting: Unevaluated property $ 234,265 $ 228,151 Evaluated property 325,068 289,851 Total oil and gas properties, at cost 559,333 518,002 Less accumulated depreciation, depletion, and amortization (32,598 ) (27,628 ) Total oil and gas properties, net $ 526,735 $ 490,374 Capitalized costs are depleted on a unit of production basis based on proved oil and natural gas reserves. Depletion expense was $5.0 million and $2.4 million for the three months ended March 31, 2019 and 2018 , respectively. Average depletion of proved properties was $10.26 per Boe and $8.09 per Boe for the three months ended March 31, 2019 and 2018 , respectively. The costs associated with unevaluated properties primarily consist of acquisition costs and capitalized general and administrative costs. Brigham Resources capitalizes certain overhead expenses and other internal costs attributable to the acquisition of mineral and royalty interests as part of its investment in oil and gas properties over the periods benefitted by these activities. Capitalized costs do not include any costs related to production and general corporate overhead or similar activities. Capitalized costs were $1.2 million and $0.8 million for the three months ended March 31, 2019 and 2018 , respectively.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2019
Related Party Transaction [Line Items]
Related Party Transactions	Related Party Transactions The July 2018 restructuring was treated as a transaction between entities under common control. There were no revenues, costs or expenses between Brigham Minerals and any related entity during the three months ended March 31, 2019 and 2018 , other than Brigham Minerals’ investment in Brigham Resources.
Brigham Resources, LLC
Related Party Transaction [Line Items]
Related Party Transactions	Related-Party Transactions Brigham Land Management (“BLM”) provides us with land brokerage services. The services are provided at market prices and are periodically verified by third party quotes. BLM is owned by Vince Brigham, an advisor to us and brother of Ben M. Brigham, our founder and Executive Chairman of our Board of Directors. For the three months ended March 31, 2019 and 2018 , the amounts paid to BLM for land brokerage services were immaterial. At March 31, 2019 and December 31, 2018 , the liabilities recorded for services performed by BLM during the respective periods were immaterial. Brigham Exploration Company (“BEXP”), partially owned by Ben M. Brigham, on occasion leases some of our acreage at market rates. There were no payments for the three months ended March 31, 2019 and 2018 .

Acquisitions and Divestitures

Acquisitions and Divestitures	3 Months Ended
	Mar. 31, 2019
Brigham Resources, LLC
Business Acquisition [Line Items]
Acquisitions and Divestitures	Acquisitions and Divestitures During the three months ended March 31, 2019 and 2018 , Brigham Resources entered into a number of individually insignificant acquisitions of mineral and royalty interests from various sellers in Texas, Oklahoma, Colorado, New Mexico, and North Dakota, as reflected in the table below. The change in the oil and natural gas property balance is comprised of individually insignificant payments for acquisitions of minerals, land brokerage costs and capitalized general and administrative expenses that were funded with borrowings under its credit facility. Assets Acquired Cash Consideration Evaluated Unevaluated Paid (In thousands) Quarter Ended March 31, 2019 $ 27,929 $ 13,403 $ 41,332 Assets Acquired Cash Consideration Evaluated Unevaluated Paid (In thousands) Quarter Ended March 31, 2018 $ 14,132 $ 11,462 $ 25,594

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2019
Loss Contingencies [Line Items]
Commitments and Contingencies	Commitments and Contingencies Brigham Minerals may, from time to time, be a party to certain lawsuits and claims arising in the ordinary course of business. The outcome of such lawsuits and claims cannot be estimated with certainty and management may not be able to estimate the range of possible losses. Brigham Minerals records reserves for contingencies when information available indicates that a loss is probable and the amount of the loss can be reasonably estimated. Brigham Minerals had no reserves for contingencies at March 31, 2019 and December 31, 2018 .
Brigham Resources, LLC
Loss Contingencies [Line Items]
Commitments and Contingencies	Commitments and Contingencies Commitments Brigham Resources leases office space under operating leases. Rent expense for the quarters ended March 31, 2019 and 2018 were $0.1 million and $0.1 million , respectively. Future minimum lease commitments under noncancelable operating leases at March 31, 2019 are presented below (in thousands): Year Commitment 2019 $ 421 2020 654 2021 672 2022 689 2023 474 2024 111 Total $ 3,021 Contingencies Brigham Resources may, from time to time, be a party to certain lawsuits and claims arising in the ordinary course of business. The outcome of such lawsuits and claims cannot be estimated with certainty and management may not be able to estimate the range of possible losses. Brigham Resources records reserves for contingencies when information available indicates that a loss is probable and the amount of the loss can be reasonably estimated. Brigham Resources had no reserves for contingencies at March 31, 2019 and December 31, 2018 .

Derivative Instruments

Derivative Instruments	3 Months Ended
	Mar. 31, 2019
Brigham Resources, LLC
Derivative [Line Items]
Derivative Instruments	Derivative Instruments Brigham Resources uses commodity derivative instruments to reduce its exposure to commodity price volatility for a portion of its forecasted crude oil and natural gas sales and thereby achieve a more predictable level of cash flows. None of the derivative instruments are designated as hedges. Brigham Resources does not enter into derivative instruments for speculative or trading purposes. Because the counterparties to Brigham Resources derivative instruments have investment grade credit ratings, Brigham Resources 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 as of March 31, 2019 . Although Brigham Resources does not currently anticipate nonperformance from its counterparties, it continually monitors the credit ratings of its counterparties. Concurrent with the termination of its prior revolving credit facility in July of 2018, Brigham Resources posted cash collateral of $1.4 million for its existing WTI fixed price swap contracts. As of March 31, 2019 , Brigham Resources had posted collateral in the amount of $1.6 million included in other current assets. The cash collateral was returned to Brigham Resources upon entering into a new revolving credit facility, as discussed in "Note 10 - Subsequent Events." As of March 31, 2019 , Brigham Resources had certain WTI fixed price swap contracts based on the New York Mercantile Exchange (“NYMEX”) futures index. The fair values, notional quantities and weighted-average swap prices of these contracts as of March 31, 2019 , are summarized in the table below. Description & Production Period Volume Weighted Fair Value Asset/(Liability) (Bbl) ($/Bbl) (In thousands) Crude Oil Swaps: April 2019 — June 2019 15,000 $ 63.61 $ 49 July 2019 — September 2019 15,000 $ 63.61 $ 46 October 2019 — December 2019 15,000 $ 63.61 $ 51 Total 45,000 $ 63.61 $ 146 Brigham Resources' derivative instruments are subject to master netting arrangements and are presented on a net basis in its condensed consolidated balance sheets. The following table summarizes the location and fair value of its derivative instruments as of March 31, 2019 and December 31, 2018 (in thousands): Derivative Instruments Balance Sheet Classification Gross Amount Less Group Net Amount As of March 31, 2019 Derivative assets: Commodity swaps Current derivative assets $ 146 $ — $ 146 As of December 31, 2018 Derivative assets: Commodity swaps Current derivative assets $ 1,057 $ — $ 1,057 During the three months ended March 31, 2019 , Brigham Resources had realized gains on its oil swap contracts of $0.2 million and unrealized losses of $0.9 million , respectively, included in loss on derivative instruments, net on its condensed consolidated statements of operations. During the three months ended March 31, 2018 , Brigham Resources had combined realized and unrealized losses on its oil swap contracts of $0.1 million and $0.2 million , respectively, included in loss on derivative instruments, net on its condensed consolidated statements of operations.

Equity

Equity	3 Months Ended
	Mar. 31, 2019
Equity [Abstract]
Equity	Equity Brigham Minerals was formed on June 18, 2018 to become a holding company for Brigham Resources. On July 16, 2018, certain entities affiliated with Warburg Pincus contributed all of their respective interests in Brigham Resources to Brigham Minerals in exchange for all of the outstanding shares of common stock of Brigham Minerals. Brigham Minerals completed the Offering of shares of Class A common stock to the public in April 2019. See discussion of the July 2018 restructuring in "Note 1 - Organization and Basis of Presentation" and the Offering in "Note 7 - Subsequent Events" below. As discussed in "Note 1 - Organization and Basis of Presentation" above, the July 2018 restructuring was treated as transactions between entities under common control and the financial statements of Brigham Minerals were recast to include Brigham Minerals’ 16.5% interest in Brigham Resources for all periods presented. As such, the equity interest of Brigham Resources is included in the statement of changes in equity for periods prior to the formation of Brigham Minerals. Brigham Resources Members’ Equity Capital contributions to Brigham Resources are based on capital calls, as determined by the Board of Directors of Brigham Resources. Contribution requests to each member are based on their commitment interest during that period of time, as defined in the Second Amended and Restated Limited Liability Company Agreement of Brigham Resources (the “Brigham Resources LLC Agreement”). Cash earnings on profits and any items in the nature of income or gain will be applied to the members’ capital account in accordance with their earnings interest, as defined in the Brigham Resources LLC Agreement. The cash contributed to Brigham Resources, less cash retained for working capital purposes, was used to complete various acquisitions. Each contribution is treated as an increase in equity with a corresponding increase in the balance of the equity method investment. There were no member contributions to Brigham Resources for the three months ended March 31, 2019 .

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2019
Brigham Resources, LLC
Debt Instrument [Line Items]
Long-Term Debt	Long-Term Debt Revolving Credit Facility Prior to its termination on July 27, 2018, the Minerals Subsidiaries maintained a secured revolving credit facility with a syndicate of financial institutions (the "prior revolving credit facility”), which had been amended periodically. The prior revolving credit facility had a commitment of $150 million , and a borrowing base of $70 million , subject to periodic re-determinations based on the Minerals Subsidiaries’ oil and natural gas reserves and other factors. The borrowing was re-determined semi-annually with effective dates of May 1 and November 1. In addition, the Minerals Subsidiaries were permitted to request up to one additional re-determination of the borrowing base during any fiscal year. The borrowing base and outstanding borrowings were $70 million each as of July 27, 2018. The outstanding borrowings under the prior revolving credit facility bore interest at a rate elected by the Minerals Subsidiaries that was equal to either an adjusted base rate, which was equal to the greatest of the prime rate, the Federal Funds effective rate plus 0.5% or 3-month LIBOR plus 1.0% , or an adjusted LIBOR rate with an interest period selected by the Minerals Subsidiaries, in each case, plus the applicable margin. The applicable margin ranged from 1.50% to 2.50% in the case of the adjusted base rate and from 2.50% to 3.50% in the case of LIBOR, in each case, depending on the amount of the loan outstanding in relation to the borrowing base. The Minerals Subsidiaries were obligated to pay a quarterly commitment fee ranging from 0.375% to 0.500% per year on the unused portion of the borrowing base, depending on the amount of the loan outstanding in relation to the borrowing base. Loan principal was permitted to be paid from time to time at the option of Minerals Subsidiaries without premium or penalty (other than customary LIBOR breakage). Loan principal was required to be paid back to the extent the loan amount exceeded the borrowing base at any time before maturity or the total outstanding balance upon the January 26, 2021 maturity date. The loan was secured by substantially all of the Minerals Subsidiaries’ assets. The credit agreement governing the prior revolving credit facility contained various affirmative and negative covenants, including limiting additional indebtedness, additional liens, sales of assets, mergers and consolidations, dividends and distributions, transactions with affiliates and entering into certain swap agreements. Additionally, the credit agreement required the maintenance of quarterly financial ratios as defined in the credit agreement, including total debt to EBITDAX not to exceed 4 .00 to 1 .00 and a ratio of current assets to current liabilities of no less than 1 .00 to 1 .00. Credit Facility On July 27, 2018, the prior revolving credit facility was terminated in conjunction with a new credit facility (the “credit facility”) with Owl Rock Capital Corporation ("Owl Rock") as administrative agent and collateral agent. Brigham Resources used the proceeds from the credit facility to repay the outstanding $70 million of principal under the prior revolving credit facility and to fund mineral and royalty acquisitions. Additionally, during the third quarter of 2018, Brigham Resources wrote off approximately $0.3 million of unamortized debt issuance costs that were related to the prior revolving credit facility. The credit facility is subject to customary fees, guarantees of subsidiaries, restrictions and covenants, including certain restricted payments, and is collateralized by certain oil and natural gas properties of Brigham Resources. During the three months ended March 31, 2019 , Brigham Resources did not incur any loan closing costs related to the credit facility. Structure. The credit facility provides for a $125 million initial term loan and a $75 million delayed draw term loan ("DDTL"), which is subject to certain customary conditions. In addition, a $10 million revolving credit facility is available for general corporate purposes. Interest. The credit facility bears interest at a rate per annum equal to, at Brigham Resources’ option, (a) the base rate plus 4.50% , or (b) the adjusted LIBOR rate for such interest period (subject to a 1.00% floor) plus 5.50% . Maturity. July 27, 2024. Amortization. The loans amortize in quarterly installments equal to 5.00% per annum (commencing with the quarter ending December 31, 2019), in each case, subject to certain requirements to prepay the outstanding balance of the loan with certain excess cash flows (as defined in the credit agreement governing the credit facility). As of March 31, 2019 , Brigham Resources had $185 million of outstanding borrowings under the credit facility. The credit agreement governing the credit facility also requires Brigham Resources to maintain compliance with the following financial and collateral coverage ratios: • an asset coverage ratio, which is the ratio of (a) the sum of (i) the present value of Brigham Resources' and the other loan parties' proved reserves (as set forth in the most recently delivered reserve report that are subject to a mortgage in favor of the administrative agent under the credit facility plus (ii) the Swap Mark-to-Market Value (as defined in the credit agreement) as of such date to (b) Consolidated Senior Secured First Lien Indebtedness (as defined in the credit agreement) as of such date of not less than 1.75 to 1.00 . • a debt to capitalization ratio, which is the ratio of (a) Consolidated Total Indebtedness to (b) Total Invested Capital (as defined in the credit agreement) of no more than 0.40 to 1.00. • a total net leverage ratio, which is the ratio, on a pro forma basis, of (a) Consolidated Total Indebtedness (as defined in the credit agreement) as of such date less up to $25 million of cash and certain permitted investments to (b) two times Brigham Resources' Consolidated EBITDA (as defined in the credit agreement) for the most recently completed Test Period (as defined in the credit agreement) of not more than 5.50 to 1.00 commencing on September 30, 2018, which steps down quarterly to 4.00 to 1.00 as of December 31, 2019. Brigham Resources was in compliance with all financial covenants as of March 31, 2019 . In April 2019, Brigham Resources borrowed an additional $15 million from the credit facility. On May 7, 2019, the credit facility was terminated and paid off using the proceeds generated from the Offering. See "Note 10 - Subsequent Events" below for further discussion.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2019
Brigham Resources, LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurements	Fair Value Measurements We classify financial assets and liabilities that are measured and reported at fair value on a recurring basis using a hierarchy based on the inputs used in measuring fair value. GAAP defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). We classify the inputs used to measure fair value into the following hierarchy: • Level 1: Inputs based on quoted market prices in active markets for identical assets or liabilities at the measurement date. • Level 2: Inputs based on quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets and liabilities in markets that are not active or other inputs that are observable and can be corroborated by observable market data. • Level 3: Inputs that reflect management’s best estimates and assumptions of what market participants would use in pricing the asset or liability at the measurement date. The inputs are unobservable in the market and significant to the valuation of the instruments. Changes in economic conditions or model-based valuation techniques may require the transfer of financial instruments from one fair value level to another. In such instances, the transfer would be reported at the beginning of the period in which the change occurs. Assets and Liabilities Measured at Fair Value on a Recurring Basis Our financial assets and liabilities that were accounted for at fair value on a recurring basis at March 31, 2019 and December 31, 2018 are as follows (in thousands): March 31, 2019 Level 1 Level 2 Level 3 Total Assets—commodity derivative instruments $ — $ 146 $ — $ 146 December 31, 2018 Level 1 Level 2 Level 3 Total Assets—commodity derivative instruments $ — $ 1,057 $ — $ 1,057 Our derivative instruments consist of WTI fixed price swaps carried at fair value as disclosed in "Note 5 - Derivative Instruments." Commodity derivative instruments are valued using 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 our credit quality for derivative liabilities. As such, these derivative contracts are classified within Level 2. Brigham Resources had no transfers into or out of Level 1 and no transfers into or out of Level 2 for the three months ended March 31, 2019 and 2018 . Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis Certain non-financial assets and liabilities, such as assets and liabilities acquired in a business combination, are measured at fair value on a nonrecurring basis on the acquisition date and are subject to fair value adjustments under certain circumstances. The inputs used to determine such fair value are primarily based upon internally developed cash flow models and include factors such as estimates of economic reserves, future commodity prices and a risk-adjusted discount rates, and are classified within Level 3. Fair Value of Other Financial Instruments The carrying value of cash, trade and other receivables and trade payables are considered to be representative of their respective fair values due to the short-term nature of these instruments. The carrying amount of debt outstanding pursuant to our prior revolving credit facility and current credit facility approximates fair value as interest rates on these instruments approximate current market rates. We categorized our long-term debt within Level 2 of the fair value hierarchy.

Subsequent events

Subsequent events	3 Months Ended
	Mar. 31, 2019
Subsequent Event [Line Items]
Subsequent events	Subsequent events In April 2019, Brigham Minerals completed the initial public offering of 16,675,000 shares of Class A common stock at a price to the public of $18.00 per share. This resulted in net proceeds of approximately $277.4 million , after deducting underwriting commissions and discounts and offering expenses. As a result of the Offering, Brigham Minerals became a holding company whose sole material asset consists of a 43.3% interest in Brigham LLC, which wholly owns Brigham Resources. Brigham Resources continues to wholly own the Minerals Subsidiaries, which own all of Brigham Resources' operating assets. In connection with the Offering, Brigham Minerals became the sole managing member of Brigham LLC and is responsible for all operational, management and administrative decisions relating to Brigham LLC’s business and will consolidate the financial results of Brigham LLC and its wholly-owned subsidiary, Brigham Resources. All of the interests in Brigham Operating were distributed, directly or indirectly, to the Existing Owners prior to the consummation of the Offering. As a result, neither Brigham Minerals nor Brigham LLC owned any direct or indirect interest in Brigham Operating at the time of the Offering. In connection with the Offering, • all of the outstanding membership interests in Brigham LLC were converted into a single class of common units in Brigham LLC (the “Brigham LLC Units”); • Brigham Minerals issued shares of Class A common stock to certain of our Existing Owners in exchange for incentive units in Brigham Equity Holdings; • Brigham Equity Holdings distributed all of its equity interests in Brigham LLC, other than its interests in Brigham LLC attributable to certain unvested incentive units in Brigham Equity Holdings, to the Existing Owners and Brigham Minerals (which resulted in the ownership in Brigham LLC of our Existing Owners with respect to unvested incentive units remaining consolidated in Brigham Equity Holdings); • Brigham Minerals issued 16,675,000 shares of Class A common stock, including the Underwriters' overallotment, to purchasers in the Offering in exchange for the proceeds of the Offering; • Each holder of Brigham LLC Units following the restructuring (a “Brigham Unit Holder”), other than Brigham Minerals and its subsidiaries, received a number of shares of Class B common stock equal to the number of Brigham LLC Units held by such Brigham Unit Holder following the Offering; and • Brigham Minerals contributed, directly or indirectly, the net proceeds of the Offering to Brigham LLC in exchange for an additional number of Brigham LLC Units such that Brigham Minerals holds, directly or indirectly, a total number of Brigham LLC Units equal to the number of shares of Class A common stock outstanding following the Offering. After the transactions discussed above and after the Offering, • the Existing Owners own all of Brigham Minerals' Class B common stock, representing 56.7% of Brigham Minerals' capital stock; • the Existing Owners own 5,322,198 shares, or 24.2% , of Brigham Minerals' Class A common stock, representing 10.5% of Brigham Minerals' capital stock; • investors in the Offering own 16,675,000 shares, or 75.8% , of Brigham Minerals' Class A common stock, representing 32.8% of Brigham Minerals' capital stock; • Brigham Minerals owns an approximate 43.3% interest in Brigham LLC; and • the Existing Owners own directly an approximate 56.7% interest in Brigham LLC (in addition to the 10.5% interest in Brigham LLC our Existing Owner own directly through their ownership of shares of Brigham Minerals' Class A common stock). Brigham LLC used a portion of the net proceeds from the Offering, which were contributed to it by Brigham Minerals to repay the $200.0 million of outstanding borrowings under the Brigham Resources credit facility and a $2.3 million prepayment premium fee related to early extinguishment of debt. Brigham Minerals has evaluated subsequent events through the date the financial statements were available to be issued.
Brigham Resources, LLC
Subsequent Event [Line Items]
Subsequent events	Subsequent Events Initial Public Offering In April 2019, Brigham Minerals completed the initial public offering of 16,675,000 shares of Class A common stock at a price to the public of $18.00 per share. Following the Offering, Brigham Resources: • wrote-off $4.1 million of capitalized debt issuance cost and incurred a $2.3 million prepayment fee, resulting in a loss on extinguishment of debt of approximately $6.4 million in its statement of operations during the second quarter of 2019; • applied capitalized issuance cost of $4.9 million as a reduction of additional paid-in-capital; and • recognized a charge for stock compensation expense of approximately $56.3 million related to the estimated fair value of the management incentive units at the closing of the Offering based on the IPO price per share, all of which was non-cash. In addition, as the vesting conditions of the unvested incentive units are satisfied, Brigham Minerals will recognize additional non-cash charges for stock compensation expense of approximately $8.2 million . Immediately prior to the consummation of the Offering, Brigham Resources distributed, directly or indirectly, to the Existing Owners all of its interests in Brigham Operating. As a result, neither Brigham Minerals nor Brigham LLC owned any direct or indirect interest in Brigham Operating at the time of the Offering. As of March 31, 2019 , Brigham Resources had $185 million of outstanding borrowings under the credit facility. In April 2019, Brigham Resources borrowed an additional $15.0 million from the credit facility, which increased the outstanding borrowings under the credit facility to $200.0 million . On May 7, 2019, Brigham Resources fully repaid the $200.0 million outstanding balance under the credit facility and a $2.3 million prepayment fee related to early extinguishment of debt with a portion of the net proceeds from the Offering that Brigham Minerals contributed to it. For further discussion, see "Note 7 - Subsequent Events" from the financial statements of Brigham Minerals, Inc. included elsewhere in this Quarterly Report. New Revolving Credit Facility On May 16, 2019 (the “closing date”) Brigham Resources entered into a credit agreement with Wells Fargo Bank, N.A., as administrative agent for the various lenders from time to time party thereto, providing for a new revolving credit facility (our “new revolving credit facility”). Our new revolving credit facility is guaranteed by Brigham Resources’ domestic subsidiaries and is collateralized by a lien on substantially all of Brigham Resources and its domestic subsidiaries’ assets, including substantially all of their respective royalty and mineral properties. Availability under our new revolving credit facility is governed by a borrowing base, which is subject to redetermination on August 1, 2019, November 1, 2019, February 1, 2020, and semi-annually thereafter on May 1 and November 1 of each year, commencing with May 1, 2020. In addition, lenders holding two-thirds of the aggregate commitments may request one additional redetermination each year. Brigham Resources can also request one additional redetermination each year, and such other redeterminations as appropriate when significant acquisition opportunities arise. The borrowing base is subject to further adjustments for asset dispositions, material title deficiencies, certain terminations of hedge agreements and issuances of permitted additional indebtedness. Increases to the borrowing base require unanimous approval of the lenders, while decreases only require approval of lenders holding two-thirds of the aggregate commitments at such time. As of the closing date, the borrowing base was $120 million and there were no amounts drawn under our new revolving credit facility. Our new revolving credit facility bears interest at a rate per annum equal to, at our option, the adjusted base rate or the adjusted LIBOR rate plus an applicable margin. The applicable margin is based on utilization of our new revolving credit facility and ranges from (a) in the case of adjusted base rate loans, 0.750% to 1.750% and (b) in the case of adjusted LIBOR rate loans, 1.750% to 2.750% . Brigham Resources may elect an interest period of one, two, three, six, or if available to all lenders, twelve months. Interest is payable in arrears at the end of each interest period, but no less frequently than quarterly. A commitment fee is payable quarterly in arrears on the daily undrawn available commitments under our new revolving credit facility in an amount ranging from 0.375% to 0.500% based on utilization of our new revolving credit facility. Our new revolving credit facility is subject to other customary fee, interest and expense reimbursement provisions. Our new revolving credit facility matures on May 16, 2024. Loans drawn under our new revolving credit facility may be prepaid at any time without premium or penalty (other than customary LIBOR breakage) and must be prepaid in the event that exposure exceeds the lesser of the borrowing base and the elected availability at such time. The principal amount of loans that are prepaid are required to be accompanied by accrued and unpaid interest and fees on such amounts. Loans that are prepaid may be reborrowed. In addition, Brigham Resources may permanently reduce or terminate in full the commitments under our new revolving credit facility prior to maturity. Any excess exposure resulting from such permanent reduction or termination must be prepaid. Upon the occurrence of an event of default under our new revolving credit facility, the administrative agent acting at the direction of the lenders holding a majority of the aggregate commitments at such time may accelerate outstanding loans and terminate all commitments under our new revolving credit facility, provided that such acceleration and termination occurs automatically upon the occurrence of a bankruptcy or insolvency event of default. Our new revolving credit facility contains customary affirmative and negative covenants, including, without limitation, reporting obligations, restrictions on asset sales, restrictions on additional debt and lien incurrence and restrictions on making distributions (subject only to no default or borrowing base deficiency) and investments. In addition, our new revolving credit facility requires us to maintain (a) a current ratio of not less than 1.00 to 1.00 and (b) a ratio of total net funded debt to consolidated EBITDA of not more than 4.00 to 1.00.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Recently Issued Accounting Standards	Recently Issued Accounting Standards In January 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2017-01, Clarifying the Definition of a Business. This guidance assists in determining whether a transaction should be accounted for as an acquisition or disposal of assets or as a business. This ASU provides a screen that when substantially all of the fair value of the gross assets acquired, or disposed of, are concentrated in a single identifiable asset, or a group of similar identifiable assets, the set will not be considered a business. If the screen is not met, a set must include an input and a substantive process that together significantly contribute to the ability to create an output to be considered a business. The new standard becomes effective for us during the fiscal year ending December 31, 2019 and interim periods within the fiscal year ending December 31, 2020 and is required to be adopted using a prospective approach. Although early application is permitted, we have not adopted ASU 2017-01 early. The implementation of the new standard is not anticipated to have a material impact on the condensed consolidated financial statements. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows, which amends ASC 230 to add or clarify guidance on the classification and presentation of restricted cash in the statement of cash flows. The ASU requires entities to show the changes in the total of cash, cash equivalents, restricted cash and restricted cash equivalents in the statement of cash flows. As a result, entities will no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statement of cash flows. The new standard becomes effective for us during the fiscal year ended December 31, 2019 and interim periods within the fiscal year ending December 31, 2020 and is required to be adopted utilizing retrospective application. Although early application is permitted, we have not adopted ASU 2016-18 early. In February 2016, the FASB issued ASU 2016-02, Leases, which requires all leasing arrangements to be presented in the balance sheet as liabilities along with a corresponding asset. ASU 2016-02 does not apply to leases of mineral rights to explore for or use crude oil and natural gas. The ASU will replace most existing lease guidance in GAAP when it becomes effective. In January 2018, the FASB issued ASU 2018-01, Land Easement Practical Expedient for Transition to Topic 842, to provide an optional practical expedient to not evaluate existing or expired land easements that were not previously accounted for as leases under Topic 840. In July 2018, the FASB issued ASU 2018-11 Leases (Topic 842): Targeted Improvements, which provides for another transition method, in addition to the existing transition method, by allowing entities to initially apply the new leases standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption (i.e. comparative periods presented in the financial statements will continue to be in accordance with current GAAP (Topic 840, Leases)). The new standard becomes effective for us during the fiscal year ending December 31, 2020 and interim periods within the fiscal year ending December 31, 2021 and early adoption is permitted. We are currently evaluating the impact, if any, that the adoption of this update will have on our consolidated financial statements and related disclosures. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. This ASU supersedes the revenue recognition requirements in Topic 605, Revenue Recognition, and industry-specific guidance in Subtopic 932-605, Extractive Activities-Oil and Gas-Revenue Recognition, and requires an entity to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration the entity expects to be entitled to in exchange for those goods or services. Consistent with our status as an emerging growth company, ASU 2014-09 becomes effective for us for the fiscal year ending on December 31, 2019 and interim periods within the fiscal year ending December 31, 2020. We intend to adopt the standard using the modified retrospective approach. We completed our review of revenue contracts covering our material revenue streams, designed to evaluate any potential changes in revenue recognition upon adoption of the new standard, and concluded that the implementation of the new standard will not have a material impact on the consolidated financial statements. We also evaluated the information technology and internal control changes that may be required to implement the new standard based on the results of our contract review process.
Investment in equity method investee	Investment in equity method investee Brigham Minerals accounts for its 16.5% investment in Brigham Resources using the equity method. Under the equity method, carrying value is adjusted for Brigham Minerals’ share of the investee’s earnings and losses, as well as capital contributions and distributions from the investee. Distributions in excess of equity method earnings are recognized as a return of investment and recorded as investing cash inflows in the accompanying statements of cash flows.
Use of estimates	Use of estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities in the financial statements and accompanying notes. Although management believes these estimates are reasonable, actual results could differ from these estimates. Changes in estimates are recorded prospectively.
Income Taxes	Income Taxes The Company accounts for income taxes using the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are calculated by applying existing tax laws and the rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. Brigham Resources, the Company’s predecessor, is a limited liability company that is not subject to U.S. federal income tax. As part of the July 2018 restructuring, certain entities affiliated with Warburg Pincus contributed all of their respective interests in certain wholly owned “blocker” entities through which they held interests in Brigham Resources to Brigham Minerals in exchange for all of the outstanding shares of common stock of Brigham Minerals. On the date of the July 2018 restructuring, a corresponding “first day” tax charge of approximately $3.1 million was recorded to establish a net deferred tax liability for differences between the tax and book basis of the investment in Brigham Resources. The offset of the deferred tax liability was recorded to additional paid-in-capital. Brigham Minerals is a corporation and it is subject to U.S. federal income tax. The tax implications of the July 2018 restructuring and the tax impact of Brigham Minerals’ status as a taxable corporation subject to U.S. federal income tax have been reflected in the accompanying financial statements.
Brigham Resources, LLC
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Recently Issued Accounting Standards	Recently Issued Accounting Standards Brigham Minerals’ status as an emerging growth company under Section 107 of the JOBS Act permits it to delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. Brigham Minerals is choosing to take advantage of this extended transition period and, as a result, Brigham Minerals and Brigham Resources will comply with new or revised accounting standards on the relevant dates on which adoption of such standards is required for private companies. In January 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2017-01, Clarifying the Definition of a Business. This guidance assists in determining whether a transaction should be accounted for as an acquisition or disposal of assets or as a business. This ASU provides a screen that when substantially all of the fair value of the gross assets acquired, or disposed of, are concentrated in a single identifiable asset, or a group of similar identifiable assets, the set will not be considered a business. If the screen is not met, a set must include an input and a substantive process that together significantly contribute to the ability to create an output to be considered a business. The new standard becomes effective for us during the fiscal year ending December 31, 2019 and interim periods within the fiscal year ending December 31, 2020 and is required to be adopted using a prospective approach. Although early application is permitted, we have not adopted ASU 2017-01 early. The implementation of the new standard is not anticipated to have a material impact on the condensed consolidated financial statements. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows, which amends ASC 230 to add or clarify guidance on the classification and presentation of restricted cash in the statement of cash flows. The ASU requires entities to show the changes in the total of cash, cash equivalents, restricted cash and restricted cash equivalents in the statement of cash flows. As a result, entities will no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statement of cash flows. The new standard becomes effective for us during the fiscal year ended December 31, 2019 and interim periods within the fiscal year ending December 31, 2020 and is required to be adopted utilizing retrospective application. Although early application is permitted, we have not adopted ASU 2016-18 early. In February 2016, the FASB issued ASU 2016-02, Leases, which requires all leasing arrangements to be presented in the balance sheet as liabilities along with a corresponding asset. ASU 2016-02 does not apply to leases of mineral rights to explore for or use crude oil and natural gas. The ASU will replace most existing lease guidance in GAAP when it becomes effective. In January 2018, the FASB issued ASU 2018-01, Land Easement Practical Expedient for Transition to Topic 842, to provide an optional practical expedient to not evaluate existing or expired land easements that were not previously accounted for as leases under Topic 840. In July 2018, the FASB issued ASU 2018-11 Leases (Topic 842): Targeted Improvements, which provides for another transition method, in addition to the existing transition method, by allowing entities to initially apply the new leases standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption (i.e. comparative periods presented in the financial statements will continue to be in accordance with current GAAP (Topic 840, Leases)). The new standard becomes effective for us during the fiscal year ending December 31, 2020 and interim periods within the fiscal year ending December 31, 2021 and early adoption is permitted. We are currently evaluating the impact, if any, that the adoption of this update will have on our consolidated financial statements and related disclosures.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	The components of the income tax provision were as follows for the periods indicated: Three Months Ended March 31, 2019 2018 (In thousands) Federal Current $ 33 $ — Deferred 112 — Total federal expense 145 — State Current 3 — Deferred 11 — Total state expense 14 — Total income tax provision $ 159 $ — The following table reconciles the income tax provision with income tax expense at the federal statutory rate for the periods indicated: Three Months Ended March 31, 2019 2018 (In thousands) Income (Loss) before income taxes $ 693 $ — Income tax at the federal statutory rate 146 — State income taxes, net of federal benefit 18 — Percentage depletion in excess of basis (5 ) Total income tax provision $ 159 $ —
Schedule of Deferred Tax Assets and Liabilities	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities were as follows: March 31, 2019 December 31, 2018 (In thousands) Noncurrent: Deferred tax assets: $ — $ — Total noncurrent deferred tax assets — — Deferred tax liabilities: Investment in subsidiary 3,598 3,476 Total noncurrent deferred tax liabilities 3,598 3,476 Net noncurrent deferred tax liability $ 3,598 $ 3,476

Equity method investment (Table

Equity method investment (Tables)	3 Months Ended
	Mar. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Below is a roll forward of the investment balance for the three months ended March 31, 2019 and 2018 (in thousands). All deemed contributions and distributions are non-cash. Balance-December 31, 2018 $ 62,388 Income from equity method investment 693 Balance-March 31, 2019 $ 63,081 Balance-December 31, 2017 $ 49,933 Income from equity method investment 1,354 Deemed contributions from equity method investee 3,573 Deemed distributions (702 ) Other comprehensive income (113 ) Balance-March 31, 2018 $ 54,045

Oil and Gas Properties (Tables)

Oil and Gas Properties (Tables)	3 Months Ended
	Mar. 31, 2019
Brigham Resources, LLC
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Schedule of Oil and Gas Properties	Oil and gas properties consisted of the following: March 31, December 31, (In thousands) Oil and gas properties, at cost, using the full cost method of accounting: Unevaluated property $ 234,265 $ 228,151 Evaluated property 325,068 289,851 Total oil and gas properties, at cost 559,333 518,002 Less accumulated depreciation, depletion, and amortization (32,598 ) (27,628 ) Total oil and gas properties, net $ 526,735 $ 490,374

Acquisitions and Divestitures (

Acquisitions and Divestitures (Tables)	3 Months Ended
	Mar. 31, 2019
Brigham Resources, LLC
Business Acquisition [Line Items]
Schedule of Asset Acquisitions	Assets Acquired Cash Consideration Evaluated Unevaluated Paid (In thousands) Quarter Ended March 31, 2019 $ 27,929 $ 13,403 $ 41,332 Assets Acquired Cash Consideration Evaluated Unevaluated Paid (In thousands) Quarter Ended March 31, 2018 $ 14,132 $ 11,462 $ 25,594

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2019
Brigham Resources, LLC
Loss Contingencies [Line Items]
Schedule of Future Minimum Lease Commitments	Future minimum lease commitments under noncancelable operating leases at March 31, 2019 are presented below (in thousands): Year Commitment 2019 $ 421 2020 654 2021 672 2022 689 2023 474 2024 111 Total $ 3,021

Derivative Instruments (Tables)

Derivative Instruments (Tables) - Brigham Resources, LLC	3 Months Ended
	Mar. 31, 2019
Derivative [Line Items]
Schedule of Derivative Instruments	The fair values, notional quantities and weighted-average swap prices of these contracts as of March 31, 2019 , are summarized in the table below. Description & Production Period Volume Weighted Fair Value Asset/(Liability) (Bbl) ($/Bbl) (In thousands) Crude Oil Swaps: April 2019 — June 2019 15,000 $ 63.61 $ 49 July 2019 — September 2019 15,000 $ 63.61 $ 46 October 2019 — December 2019 15,000 $ 63.61 $ 51 Total 45,000 $ 63.61 $ 146
Offsetting Liabilities	The following table summarizes the location and fair value of its derivative instruments as of March 31, 2019 and December 31, 2018 (in thousands): Derivative Instruments Balance Sheet Classification Gross Amount Less Group Net Amount As of March 31, 2019 Derivative assets: Commodity swaps Current derivative assets $ 146 $ — $ 146 As of December 31, 2018 Derivative assets: Commodity swaps Current derivative assets $ 1,057 $ — $ 1,057

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2019
Brigham Resources, LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	Our financial assets and liabilities that were accounted for at fair value on a recurring basis at March 31, 2019 and December 31, 2018 are as follows (in thousands): March 31, 2019 Level 1 Level 2 Level 3 Total Assets—commodity derivative instruments $ — $ 146 $ — $ 146 December 31, 2018 Level 1 Level 2 Level 3 Total Assets—commodity derivative instruments $ — $ 1,057 $ — $ 1,057

Business and Basis of Presentat

Business and Basis of Presentation (Details)	3 Months Ended
	Mar. 31, 2019segmentbusiness	Jul. 16, 2018
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	16.50%
Number of operating segments	1
Brigham Resources, LLC
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage		16.50%
Number of operating segments	1
Number Of Lines Of Business | business	2
Brigham Resources
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	16.50%	16.50%

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Mar. 31, 2019	Jul. 31, 2018
Accounting Policies [Abstract]
Equity method investment, ownership percentage		16.50%
Net deferred tax liability resulting from corporate reorganization	$ 3,476	$ 3,598	$ 3,100
Effective income tax rate (as a percent)	23.00%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Federal and State Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Federal
Current	$ 33	$ 0
Deferred	112	0
Total federal expense	145	0
State
Current	3	0
Deferred	11	0
Total state expense	14	0
Total income tax provision	$ 159	$ 0

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Reconciliation of Income Tax Expense with Income Tax Provision (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accounting Policies [Abstract]
Income (Loss) before income taxes	$ 693	$ 0
Income tax at the federal statutory rate	146	0
State income taxes, net of federal benefit	18	0
Percentage depletion in excess of basis	(5)
Total income tax provision	$ 159	$ 0

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Jul. 31, 2018
Deferred Tax Assets, Gross [Abstract]
Deferred tax assets:	$ 0	$ 0
Total noncurrent deferred tax assets	0	0
Deferred Tax Liabilities, Gross [Abstract]
Investment in subsidiary	3,598	3,476
Total noncurrent deferred tax liabilities	3,598	3,476
Net noncurrent deferred tax liability	$ 3,598	$ 3,476	$ 3,100

Equity method investment (Detai

Equity method investment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	16.50%
Increase (Decrease) in Equity Method Investments [Roll Forward]
Beginning balance	$ 62,388
Income from equity method investment	693	$ 1,354
Ending balance	63,081
Brigham Resources, LLC
Increase (Decrease) in Equity Method Investments [Roll Forward]
Beginning balance	62,388	49,933
Income from equity method investment	693	1,354
Deemed contributions from equity method investee		3,573
Deemed distributions		(702)
Other comprehensive income		(113)
Ending balance	$ 63,081	$ 54,045

Oil and Gas Properties - Schedu

Oil and Gas Properties - Schedule of Oil and Gas Properties (Details) - Brigham Resources, LLC - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Oil and gas properties, at cost, using the full cost method of accounting:
Unevaluated property	$ 234,265	$ 228,151
Evaluated property	325,068	289,851
Total oil and gas properties, at cost	559,333	518,002
Less accumulated depreciation, depletion, and amortization	(32,598)	(27,628)
Total oil and gas properties, net	$ 526,735	$ 490,374

Oil and Gas Properties - Narrat

Oil and Gas Properties - Narrative (Details) - Brigham Resources, LLC $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)$ / Boe	Mar. 31, 2018USD ($)$ / Boe
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Depletion expense	$ 5	$ 2.4
Average depletion of proved properties (in dollars per Boe) | $ / Boe	10.26	8.09
Capitalized costs	$ 1.2	$ 0.8

Acquisitions and Divestitures_2

Acquisitions and Divestitures (Details) - Brigham Resources, LLC - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Business Acquisition [Line Items]
Assets acquired, evaluated	$ 27,929	$ 14,132
Assets acquired, unevaluated	13,403	11,462
Cash consideration paid	$ 41,332	$ 25,594

Commitments and Contingencies_2

Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Rent expense	$ 100	$ 100
2019	421
2020	654
2021	672
2022	689
2023	474
2024	111
Total	$ 3,021

Derivative Instruments - Narrat

Derivative Instruments - Narrative (Details) - Brigham Resources, LLC - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Jul. 27, 2018
Derivative [Line Items]
Cash collateral posted for existing swap contracts	$ 1.6		$ 1.4
Commodity swaps
Derivative [Line Items]
Loss on derivative instruments, net	(0.2)	$ 0.1
Unrealized losses on oil swap contracts	$ 0.9	$ 0.2

Derivative Instruments - Summar

Derivative Instruments - Summary of Notional Amounts of Derivatives (Details) - Brigham Resources, LLC $ in Thousands	3 Months Ended
	Mar. 31, 2019USD ($)$ / bblbbl
Derivative [Line Items]
Volume | bbl	45,000
Weighted Average Swap Price | $ / bbl	63.61
Fair Value Asset/(Liability) | $	$ 146
April 2019 — June 2019
Derivative [Line Items]
Volume | bbl	15,000
Weighted Average Swap Price | $ / bbl	63.61
Fair Value Asset/(Liability) | $	$ 49
July 2019 — September 2019
Derivative [Line Items]
Volume | bbl	15,000
Weighted Average Swap Price | $ / bbl	63.61
Fair Value Asset/(Liability) | $	$ 46
October 2019 — December 2019
Derivative [Line Items]
Volume | bbl	15,000
Weighted Average Swap Price | $ / bbl	63.61
Fair Value Asset/(Liability) | $	$ 51

Derivative Instruments - Summ_2

Derivative Instruments - Summary of Location and Fair Value of Derivative Instruments (Details) - Brigham Resources, LLC - Commodity swaps - Current derivative assets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Gross Amount Recognized	$ 146	$ 1,057
Less Group Amount of Offset	0	0
Net Amount Recognized	$ 146	$ 1,057

Equity (Details)

Equity (Details)	Mar. 31, 2019	Jul. 16, 2018
Class of Stock [Line Items]
Equity method investment, ownership percentage	16.50%
Brigham Resources
Class of Stock [Line Items]
Equity method investment, ownership percentage	16.50%	16.50%

Long-Term Debt (Details)

Long-Term Debt (Details)	Jul. 27, 2018USD ($)	Apr. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Sep. 30, 2018USD ($)	Dec. 31, 2019	Apr. 02, 2019USD ($)	Jul. 26, 2018USD ($)
Subsequent Event
Debt Instrument [Line Items]
Unamortized debt issuance costs written off		$ 4,100,000
Subsequent Event | Term Loan Facility
Debt Instrument [Line Items]
Long-term line of credit						$ 200,000,000
Brigham Resources, LLC | Term Loan Facility
Debt Instrument [Line Items]
Line of credit, borrowing base	$ 125,000,000
Long-term line of credit			$ 185,000,000
Debt instrument, amortization, quarterly installments, percent			5.00%
Debt instrument, covenant, asset coverage ratio, minimum			1.75
Debt instrument, covenant, debt to capitalization ratio, maximum			0.40
Total net leverage ratio, maximum cash reduction to ratio			$ 25,000,000
Debt instrument, covenant, total net leverage ratio, maximum			5.50
Brigham Resources, LLC | Term Loan Facility | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)			5.50%
Brigham Resources, LLC | Term Loan Facility | London Interbank Offered Rate (LIBOR) | Minimum
Debt Instrument [Line Items]
Interest rate, floor (as a percent)			1.00%
Brigham Resources, LLC | Term Loan Facility | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)			4.50%
Brigham Resources, LLC | Delayed Draw Term Loan
Debt Instrument [Line Items]
Line of credit, borrowing base	75,000,000
Brigham Resources, LLC | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit, borrowing base							$ 150,000,000
Long-term debt outstanding	70,000,000
Debt instrument, covenant, debt to EBITDAX ratio, maximum			4
Debt instrument, covenant, current ratio, minimum			1
Unamortized debt issuance costs written off				$ 300,000
Line of credit facility available	70,000,000
Brigham Resources, LLC | Revolving Credit Facility | Minimum
Debt Instrument [Line Items]
Commitment fee, percentage			0.375%
Brigham Resources, LLC | Revolving Credit Facility | Maximum
Debt Instrument [Line Items]
Commitment fee, percentage			0.50%
Brigham Resources, LLC | Revolving Credit Facility | Federal Funds Effective Swap Rate
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)			0.50%
Brigham Resources, LLC | Revolving Credit Facility | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)			1.00%
Brigham Resources, LLC | Revolving Credit Facility | London Interbank Offered Rate (LIBOR) | Minimum
Debt Instrument [Line Items]
Applicable margin on variable rate			2.50%
Brigham Resources, LLC | Revolving Credit Facility | London Interbank Offered Rate (LIBOR) | Maximum
Debt Instrument [Line Items]
Applicable margin on variable rate			3.50%
Brigham Resources, LLC | Revolving Credit Facility | Adjusted Base Rate | Minimum
Debt Instrument [Line Items]
Applicable margin on variable rate			1.50%
Brigham Resources, LLC | Revolving Credit Facility | Adjusted Base Rate | Maximum
Debt Instrument [Line Items]
Applicable margin on variable rate			2.50%
Brigham Resources, LLC | Revolving Credit Facility | Term Loan Facility
Debt Instrument [Line Items]
Line of credit, borrowing base	$ 10,000,000
Brigham Resources, LLC | Scenario, Forecast | Term Loan Facility
Debt Instrument [Line Items]
Debt instrument, covenant, total net leverage ratio, maximum					4
Brigham Resources, LLC | Subsequent Event | Term Loan Facility
Debt Instrument [Line Items]
Borrowings from credit facility		$ 15,000,000

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value (Details) - Brigham Resources, LLC - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets—commodity derivative instruments	$ 146	$ 1,057
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets—commodity derivative instruments	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets—commodity derivative instruments	146	1,057
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets—commodity derivative instruments	$ 0	$ 0

Subsequent events (Details)

Subsequent events (Details)	May 16, 2019USD ($)	May 07, 2019USD ($)	Apr. 02, 2019USD ($)	Apr. 30, 2019USD ($)$ / sharesshares	Mar. 31, 2019USD ($)	Mar. 31, 2018USD ($)	Jul. 27, 2018USD ($)
Subsequent Event
Subsequent Event [Line Items]
Prepayment premium paid				$ 2,300,000
Unamortized debt issuance costs written off				4,100,000
Loss on extinguishment of debt				6,400,000
Capitalized issuance costs				4,900,000
Stock compensation expense				56,300,000
Additional non-cash charge for stock compensation expense				8,200,000
Term Loan Facility | Subsequent Event
Subsequent Event [Line Items]
Prepayment premium paid		$ 2,300,000
Borrowings of long-term debt			$ 15,000,000
Long-term line of credit			$ 200,000,000
Initial Public Offering | Subsequent Event
Subsequent Event [Line Items]
Consideration received				$ 277,400,000
Common Class A | Initial Public Offering | Subsequent Event
Subsequent Event [Line Items]
Sale of stock, number of shares issued | shares				16,675,000
Sale of stock, price per share (in dollars per share) | $ / shares				$ 18
Brigham Resources, LLC
Subsequent Event [Line Items]
Borrowings of long-term debt					$ 10,000,000	$ 13,000,000
Brigham Resources, LLC | Term Loan Facility
Subsequent Event [Line Items]
Long-term line of credit					$ 185,000,000
Line of credit, borrowing base							$ 125,000,000
Brigham Resources, LLC | New Revolving Credit Facility | Subsequent Event
Subsequent Event [Line Items]
Line of credit, borrowing base	$ 120,000,000
Debt instrument, covenant, current ratio, minimum	1
Debt instrument, covenant, total net funded debt to consolidated EBITDA ratio, maximum	4
Brigham LLC | Subsequent Event
Subsequent Event [Line Items]
Ownership percentage by subsidiary				43.30%
Existing Owners of Brigham Minerals | Subsequent Event
Subsequent Event [Line Items]
Sale of stock, ownership percentage				10.50%
Existing Owners of Brigham Minerals | Common Class A | Subsequent Event
Subsequent Event [Line Items]
Sale of stock, ownership percentage				24.20%
Number of shares owned | shares				5,322,198
Existing Owners of Brigham Minerals | Common Class B | Subsequent Event
Subsequent Event [Line Items]
Sale of stock, ownership percentage				56.70%
Investors in Offering | Subsequent Event
Subsequent Event [Line Items]
Sale of stock, ownership percentage				32.80%
Investors in Offering | Common Class A | Subsequent Event
Subsequent Event [Line Items]
Sale of stock, ownership percentage				75.80%
Number of shares owned | shares				16,675,000
Minimum | Brigham Resources, LLC | New Revolving Credit Facility | Subsequent Event
Subsequent Event [Line Items]
Commitment fee, percentage	0.375%
Maximum | Brigham Resources, LLC | New Revolving Credit Facility | Subsequent Event
Subsequent Event [Line Items]
Commitment fee, percentage	0.50%
Adjusted Base Rate | Minimum | Brigham Resources, LLC | New Revolving Credit Facility | Subsequent Event
Subsequent Event [Line Items]
Basis spread on variable rate (as a percent)	0.75%
Adjusted Base Rate | Maximum | Brigham Resources, LLC | New Revolving Credit Facility | Subsequent Event
Subsequent Event [Line Items]
Basis spread on variable rate (as a percent)	1.75%
London Interbank Offered Rate (LIBOR) | Brigham Resources, LLC | Term Loan Facility
Subsequent Event [Line Items]
Basis spread on variable rate (as a percent)					5.50%
London Interbank Offered Rate (LIBOR) | Minimum | Brigham Resources, LLC | New Revolving Credit Facility | Subsequent Event
Subsequent Event [Line Items]
Basis spread on variable rate (as a percent)	1.75%
London Interbank Offered Rate (LIBOR) | Maximum | Brigham Resources, LLC | New Revolving Credit Facility | Subsequent Event
Subsequent Event [Line Items]
Basis spread on variable rate (as a percent)	2.75%