Solaris Energy Infrastructure (SEI) 10-Q 30 Oct 19 2019 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Oct. 25, 2019
Document Type	10-Q
Document Period End Date	Sep. 30, 2019
Entity Registrant Name	SOLARIS OILFIELD INFRASTRUCTURE, INC.
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Shell Company	false
Entity Central Index Key	0001697500
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false
Class A Common Stock
Entity Common Stock, Shares Outstanding		31,648,317
Class B Common Stock
Entity Common Stock, Shares Outstanding		15,939,169

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash	$ 51,686	$ 25,057
Accounts receivable, net	44,115	39,746
Prepaid expenses and other current assets	5,246	5,492
Inventories	7,481	10,470
Total current assets	108,528	80,765
Property, plant and equipment, net	311,253	296,538
Operating lease right-of-use assets	8,032
Goodwill	17,236	17,236
Intangible assets, net	3,956	4,540
Deferred tax assets	56,475	58,074
Other assets	660	1,454
Total assets	506,140	458,607
Current liabilities:
Accounts payable	3,502	9,127
Accrued liabilities	16,834	12,658
Current portion of deferred revenue	12,990	12,990
Current portion of operating lease liabilities	598
Current portion of finance lease liabilities	30	35
Other current liabilities	1,115	515
Total current liabilities	35,069	35,325
Senior secured credit facility		13,000
Deferred revenue, net of current	2,960	12,468
Operating lease liabilities, net of current	7,961
Finance lease liabilities, net of current	137	154
Payables related to Tax Receivable Agreement	67,987	56,149
Other long-term liabilities	494	633
Total liabilities	114,608	117,729
Commitments and contingencies (Note 11)
Stockholders' equity:
Preferred stock, $0.01 par value, 50,000 shares authorized, none issued and outstanding
Additional paid-in capital	194,153	164,086
Retained earnings	62,517	35,507
Treasury stock (at cost), 163 shares and 91 shares as of September 30, 2019 and December 31, 2018, respectively	(2,522)	(1,414)
Total stockholders' equity attributable to Solaris	254,458	198,450
Non-controlling interest	137,074	142,428
Total stockholders' equity	391,532	340,878
Total liabilities and stockholders' equity	506,140	458,607
Class A Common Stock
Stockholders' equity:
Common stock	$ 310	$ 271

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares shares in Thousands	Sep. 30, 2019	Dec. 31, 2018
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, Authorized shares	50,000	50,000
Preferred stock, issued shares	0	0
Preferred stock, outstanding shares	0	0
Treasury stock (in shares)	163	91
Class A Common Stock
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	600,000	600,000
Common stock, shares issued	31,179	27,182
Common stock, shares outstanding	31,016	27,091
Class B Common Stock
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized	180,000	180,000
Common stock, shares issued	15,940	19,627
Common stock, shares outstanding	15,940	19,627

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue:
Revenue	$ 59,604	$ 56,686	$ 178,829	$ 139,859
Operating costs and expenses:
Depreciation and amortization	6,908	5,328	19,875	12,514
Selling, general and administrative (excluding $147 and $126 and $411 and $355 of depreciation and amortization for the three and nine months ended September 30, 2019 and 2018, respectively, shown separately)	4,933	3,869	13,967	12,662
Other operating expenses	248	56	529	1,752
Total operating costs and expenses	36,811	25,896	100,985	68,747
Operating income	22,793	30,790	77,844	71,112
Interest expense, net	(8)	(116)	(775)	(271)
Total other expense	(8)	(116)	(775)	(271)
Income before income tax expense	22,785	30,674	77,069	70,841
Provision for income taxes	(3,703)	(4,237)	(12,042)	(9,541)
Net income	19,082	26,437	65,027	61,300
Less: net income related to non-controlling interests	(7,684)	(13,418)	(28,036)	(31,754)
Net income attributable to Solaris	11,398	13,019	36,991	29,546
System rental
Revenue:
Revenue	36,638	42,031	113,726	104,563
Operating costs and expenses:
Cost of revenue	2,838	1,949	7,737	5,050
Depreciation and amortization	5,773	4,133	16,481	10,128
System services
Revenue:
Revenue	18,153	12,053	48,621	29,499
Operating costs and expenses:
Cost of revenue	21,072	13,906	56,366	34,691
Depreciation and amortization	384	347	1,173	889
Transloading services
Revenue:
Revenue	4,417	2,000	15,131	3,847
Operating costs and expenses:
Cost of revenue	652	597	2,051	1,464
Depreciation and amortization	411	529	1,231	544
Inventory software services
Revenue:
Revenue	396	602	1,351	1,950
Operating costs and expenses:
Cost of revenue	160	191	460	614
Depreciation and amortization	$ 193	$ 193	$ 579	$ 598
Class A Common Stock
Operating costs and expenses:
Earnings per share of Class A common stock - basic (in dollars per share)	$ 0.36	$ 0.49	$ 1.33	$ 1.13
Earnings per share of Class A common stock - diluted (in dollars per share)	$ 0.36	$ 0.49	$ 1.33	$ 1.12
Basic weighted-average shares of Class A common stock outstanding (in shares)	30,951	26,197	27,270	25,216
Diluted weighted-average shares of Class A common stock outstanding (in shares)	30,980	26,329	27,317	25,380

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Depreciation and amortization	$ 6,908	$ 5,328	$ 19,875	$ 12,514
Stock-based compensation expense	1,225	338	3,265	3,140
Debt issuance costs written-off			528
Selling, general and administrative expenses
Depreciation and amortization	147	126	411	355
Stock-based compensation expense	1,139	286	3,042	3,002
System rental
Depreciation and amortization	5,773	4,133	16,481	10,128
Stock-based compensation expense	10		24	5
System services
Depreciation and amortization	384	347	1,173	889
Stock-based compensation expense	71	51	187	132
Transloading services
Depreciation and amortization	411	529	1,231	544
Stock-based compensation expense	5	1	12	1
Inventory software services
Depreciation and amortization	$ 193	$ 193	$ 579	$ 598

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Common StockClass A Common Stock	Common StockClass B Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock	Non controlling Interest	Total
Balance at beginning of year at Dec. 31, 2017	$ 190		$ 117,638	$ (4,174)	$ (261)	$ 140,850	$ 254,243
Balance at beginning of year (in shares) at Dec. 31, 2017	19,010	26,811			16
Changes in Stockholders' Equity
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock	$ 59		31,317			(31,376)
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock (in shares)	5,904	(5,904)
Net effect of deferred tax asset and payables related to Tax Receivable Agreement from the exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock			(171)				(171)
Stock option exercises	$ 3		1,047			(374)	676
Stock option exercises (in shares)	235
Stock-based compensation			989			885	1,874
Net income				5,930		7,485	13,415
Balance at end of year at Mar. 31, 2018	$ 252		150,820	1,756	$ (261)	117,470	270,037
Balance at end of year (in shares) at Mar. 31, 2018	25,149	20,907			16
Balance at beginning of year at Dec. 31, 2017	$ 190		117,638	(4,174)	$ (261)	140,850	254,243
Balance at beginning of year (in shares) at Dec. 31, 2017	19,010	26,811			16
Changes in Stockholders' Equity
Net income							61,300
Balance at end of year at Sep. 30, 2018	$ 266		161,116	25,372	$ (1,410)	135,626	320,970
Balance at end of year (in shares) at Sep. 30, 2018	26,607	20,110			91
Balance at beginning of year at Mar. 31, 2018	$ 252		150,820	1,756	$ (261)	117,470	270,037
Balance at beginning of year (in shares) at Mar. 31, 2018	25,149	20,907			16
Changes in Stockholders' Equity
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock	$ 3		1,549			(1,552)
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock (in shares)	269	(269)
Net effect of deferred tax asset and payables related to Tax Receivable Agreement from the exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock			753				753
Stock option exercises			171			(11)	160
Stock option exercises (in shares)	56
Stock-based compensation			964			781	1,745
Vesting of restricted stock	$ 3		895			(898)
Vesting of restricted stock (in shares)	346
Other			60				60
Net income				10,597		10,851	21,448
Balance at end of year at Jun. 30, 2018	$ 258		155,212	12,353	$ (261)	126,641	294,203
Balance at end of year (in shares) at Jun. 30, 2018	25,820	20,638			16
Changes in Stockholders' Equity
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock	$ 5		3,417			(3,422)
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock (in shares)	528	(528)
Net effect of deferred tax asset and payables related to Tax Receivable Agreement from the exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock			842				842
Stock option exercises			312		$ (9)	(207)	96
Stock option exercises (in shares)	36				1
Stock-based compensation			222			310	532
Vesting of restricted stock	$ 3		1,111		$ (1,140)	(1,114)	(1,140)
Vesting of restricted stock (in shares)	223				74
Net income				13,019		13,418	26,437
Balance at end of year at Sep. 30, 2018	$ 266		161,116	25,372	$ (1,410)	135,626	320,970
Balance at end of year (in shares) at Sep. 30, 2018	26,607	20,110			91
Changes in Stockholders' Equity
Effect of ASU No. 2016-02 implementation			186	(532)		(186)	(532)
Balance at beginning of year at Dec. 31, 2018	$ 271		164,086	35,507	$ (1,414)	142,428	340,878
Balance at beginning of year (in shares) at Dec. 31, 2018	27,091	19,627			91
Changes in Stockholders' Equity
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock	$ 32		24,925			(24,957)
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock (in shares)	3,245	(3,245)
Net effect of deferred tax asset and payables related to Tax Receivable Agreement from the exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock			(1,895)				(1,895)
Stock option exercises	$ 1		601		$ (427)	(336)	(161)
Stock option exercises (in shares)	65				28
Stock-based compensation			553			346	899
Vesting of restricted stock			2		$ (4)	(2)	(4)
Solaris LLC distribution paid to Solaris LLC unitholders at $0.10 per Solaris LLC Unit						(1,638)	(1,638)
Dividends paid ($0.10 per share of Class A common stock)				(3,119)			(3,119)
Net income				12,317		11,118	23,435
Balance at end of year at Mar. 31, 2019	$ 304		188,458	44,173	$ (1,845)	126,773	357,863
Balance at end of year (in shares) at Mar. 31, 2019	30,401	16,382			119
Balance at beginning of year at Dec. 31, 2018	$ 271		164,086	35,507	$ (1,414)	142,428	340,878
Balance at beginning of year (in shares) at Dec. 31, 2018	27,091	19,627			91
Changes in Stockholders' Equity
Net income							65,027
Balance at end of year at Sep. 30, 2019	$ 310		194,153	62,517	$ (2,522)	137,074	391,532
Balance at end of year (in shares) at Sep. 30, 2019	31,016	15,940			163
Balance at beginning of year at Mar. 31, 2019	$ 304		188,458	44,173	$ (1,845)	126,773	357,863
Balance at beginning of year (in shares) at Mar. 31, 2019	30,401	16,382			119
Changes in Stockholders' Equity
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock	$ 4		3,571			(3,575)
Exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock (in shares)	442	(442)
Net effect of deferred tax asset and payables related to Tax Receivable Agreement from the exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock			(397)				(397)
Stock option exercises			48			(20)	28
Stock option exercises (in shares)	11
Stock-based compensation			809			428	1,237
Vesting of restricted stock	$ 1		245		$ (299)	(246)	(299)
Vesting of restricted stock (in shares)	51				16
Solaris LLC distribution paid to Solaris LLC unitholders at $0.10 per Solaris LLC Unit						(1,594)	(1,594)
Dividends paid ($0.10 per share of Class A common stock)				(3,164)			(3,164)
Net income				13,275		9,234	22,509
Balance at end of year at Jun. 30, 2019	$ 309		192,734	54,284	$ (2,144)	131,000	376,183
Balance at end of year (in shares) at Jun. 30, 2019	30,905	15,940			135
Changes in Stockholders' Equity
Net effect of deferred tax asset and payables related to Tax Receivable Agreement from the exchange of Solaris LLC Units and shares of Class B common stock for shares of Class A common stock			143				143
Stock-based compensation			833			429	1,262
Vesting of restricted stock	$ 1		443		$ (378)	(445)	(379)
Vesting of restricted stock (in shares)	111				28
Solaris LLC distribution paid to Solaris LLC unitholders at $0.10 per Solaris LLC Unit						(1,594)	(1,594)
Dividends paid ($0.10 per share of Class A common stock)				(3,165)			(3,165)
Net income				11,398		7,684	19,082
Balance at end of year at Sep. 30, 2019	$ 310		$ 194,153	$ 62,517	$ (2,522)	$ 137,074	$ 391,532
Balance at end of year (in shares) at Sep. 30, 2019	31,016	15,940			163

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares	Sep. 26, 2019	Jun. 26, 2019	Mar. 29, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019
CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY
Distributions paid to unit holders (in dollars per unit)				$ 0.10		$ 0.10
Cash dividends paid (in dollars per share)	$ 0.10	$ 0.10	$ 0.10	$ 0.1	$ 0.1	$ 0.1

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities:
Net income	$ 65,027	$ 61,300
Adjustment to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	19,875	12,514
Loss on disposal of asset	181	222
Stock-based compensation	3,265	3,140
Amortization of debt issuance costs	709	218
Write-off of deposit	202
Deferred income tax expense	11,284	9,000
Other	(165)	651
Changes in operating assets and liabilities:
Accounts receivable	(4,369)	(21,599)
Prepaid expenses and other assets	2,088	(3,667)
Inventories	(2,555)	(8,575)
Accounts payable	(3,909)	441
Accrued liabilities	6,424	3,894
Deferred revenue	(9,508)
Net cash provided by operating activities	88,549	57,539
Cash flows from investing activities:
Investment in property, plant and equipment	(32,914)	(125,013)
Proceeds from disposal of asset	130
Investment in intangible assets		(6)
Cash received from insurance proceeds	618	160
Net cash used in investing activities	(32,166)	(124,859)
Cash flows from financing activities:
Payments under finance leases	(26)	(21)
Payments under insurance premium financing	(1,443)	(841)
Proceeds from stock option exercises	294	932
Payments related to purchase of treasury stock	(1,108)	(1,140)
Repayment of (proceeds from) senior secured credit facility	(13,000)	8,000
Payments related to debt issuance costs	(197)	(1,014)
Distribution and dividend paid to Solaris LLC unitholders and Class A common shareholders	(14,274)
Other		60
Net cash provided by (used in) financing activities	(29,754)	5,976
Net increase (decrease) in cash	26,629	(61,344)
Cash at beginning of period	25,057	63,421
Cash at end of period	51,686	2,077
Non-cash activities
Capitalized depreciation in property, plant and equipment	559	501
Property and equipment additions incurred but not paid at period-end	235	6,309
Property, plant and equipment additions transferred from inventory	5,355	7,532
Insurance premium financing	1,869	1,552
Cash paid for:
Interest	200	118
Income taxes	$ 663	$ 314

Organization and Background of

Organization and Background of Business	9 Months Ended
	Sep. 30, 2019
Organization and Background of Business
Organization and Background of Business	1. Organization and Background of Business Description of Business We are an independent provider of supply chain management and logistics solutions designed to drive efficiencies and reduce costs for the oil and natural gas industry. We manufacture and provide patented mobile proppant and chemical management systems that unload, store and deliver proppant and chemicals used in hydraulic fracturing of oil and natural gas wells. The systems are designed to address the challenges associated with transferring large quantities of proppant and chemicals to the well site, including the cost and management of last mile logistics, which includes coordinating proppant delivery to systems. Our systems are deployed in most of the active oil and natural gas basins in the United States. We operate an independent, unit-train capable, high speed transload facility in Oklahoma (the “Kingfisher Facility”) that provides rail-to-truck transloading and high-efficiency sand silo storage and transloading services. Commercial operations at the Kingfisher Facility commenced in January 2018 and we completed construction at the end of July 2018. We also provide software solutions to remotely monitor proppant inventory from the source mine to well site through our Railtronix® and Solaris Lens™ inventory management systems. Our customers use data from our software solutions to manage distribution of proppant and chemicals throughout their supply chain.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2019
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation and Consolidation The accompanying interim unaudited condensed consolidated financial statements of Solaris Inc. have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). These financial statements reflect all normal recurring adjustments that are necessary for fair presentation. Operating results for the three and nine months ended September 30, 2019 and 2018 are not necessarily indicative of the results that may be expected for the full year or for any interim period. The unaudited interim condensed consolidated financial statements should be read in conjunction with Solaris Inc.’s Annual Report on Form 10-K/A for the year ended December 31, 2018. Solaris Oilfield Infrastructure, Inc. (either individually or together with its subsidiaries, as the context requires, “Solaris Inc.” or the “Company”) is the managing member of Solaris Oilfield Infrastructure, LLC (“Solaris LLC”) and is responsible for all operational, management and administrative decisions relating to Solaris LLC's business. Solaris Inc. consolidates the financial results of Solaris LLC and its subsidiaries and reports non-controlling interest related to the portion of the units in Solaris LLC (the “Solaris LLC Units”) not owned by Solaris Inc., which will reduce net income attributable to the holders of Solaris Inc.’s Class A common stock All material intercompany transactions and balances have been eliminated upon consolidation. Use of Estimates The preparation of condensed consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Significant estimates used in the preparation of these condensed consolidated financial statements include, but are not limited to, stock-based compensation, depreciation associated with property, plant and equipment and related impairment considerations of those assets, determination of fair value of intangible assets acquired in business combinations, determination of the present value of lease payments and right-of-use assets and certain other assets and liabilities. Actual results could differ from management’s best estimates as additional information or actual results become available in the future, and those differences could be material. Cash For the purposes of the statements of cash flows, the Company considers all short-term, highly liquid, investments with an original maturity of three months or less to be cash equivalents. Cash is deposited in demand accounts in federally insured domestic institutions to minimize risk. Accounts of each institution are insured by Federal Deposit Insurance Corporation. Cash balances at times may exceed federally-insured limits. We have not incurred losses related to these deposits. Accounts Receivable Accounts receivable consists of trade receivables recorded at the invoice amount, plus accrued revenue that is not yet billed, less an estimated allowance for doubtful accounts (if any). Accounts receivable are generally due within 60 days or less, or in accordance with terms agreed with customers. The Company considers accounts outstanding longer than the payment terms past due. The Company determines the allowance by considering a number of factors, including the length of time trade accounts receivable are past due, previous loss history, the customer’s current ability to pay its obligation, and the condition of the general economy and the industry as a whole. Accounts receivable are written off when they are deemed uncollectible, and payments subsequently received on such receivables are credited to the allowance for doubtful accounts. Allowance for doubtful accounts was zero as of September 30, 2019 and December 31, 2018. Inventories Inventories consist of materials used in the manufacturing of the Company’s systems, which include raw materials and purchased parts and is stated at the lower of cost or net realizable value. Net realizable value is determined, giving consideration to quality, excessive levels, obsolescence and other factors. Adjustments that reduce stated amounts will be recognized as impairments in the condensed consolidated statements of operations. There were no impairments recorded for the three and nine months ended September 30, 2019 and 2018. Property, Plant and Equipment Property, plant and equipment are stated at cost, or fair value for assets acquired in a business combination, less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful service lives of the assets as noted below: Useful Life Systems and related equipment Up to 15 years Machinery and equipment 3-10 years Furniture and fixtures 5 years Computer hardware and software 3-10 years Vehicles 5 years Transloading facility and equipment 15-30 years Buildings and leasehold improvements 15 years Systems that are in the process of being manufactured are considered property, plant and equipment. However, the systems do not depreciate until they are fully completed. Systems in process are a culmination of material, labor and overhead. Expenditures for maintenance and repairs are charged against income as incurred. Betterments that increase the value or materially extend the life of the related assets are capitalized. Upon sale or disposition of property and equipment, the cost and related accumulated depreciation and amortization are removed from the condensed consolidated financial statements and any resulting gain or loss is recognized in the condensed consolidated statements of operations. Definite-lived Intangible Assets Identified intangible assets with determinable lives consist primarily of customer relationships, a non-competition agreement and software acquired in the acquisition of Railtronix, LLC (“Railtronix”), as well as patents that were filed for our systems and other intellectual property. Amortization on these assets is calculated on the straight-line method over the estimated useful lives of the assets, which is five to fifteen years. The Company recorded amortization expense of $195 for each of the three months ended September 30, 2019 and 2018. The Company recorded amortization expense of $584 and $606 for the nine months ended September 30, 2019 and 2018, respectively. Identified intangible assets by major classification consist of the following: Accumulated Net Book Gross Amortization Value As of September 30, 2019: Customer relationships $ 4,703 $ (1,232) $ 3,471 Software acquired in the acquisition of Railtronix 346 (91) 255 Non-competition agreement 225 (82) 143 Patents and other 114 (27) 87 Total identifiable intangibles $ 5,388 $ (1,432) $ 3,956 As of December 31, 2018: Customer relationships $ 4,703 $ (727) $ 3,976 Software acquired in the acquisition of Railtronix 346 (54) 292 Non-competition agreement 225 (49) 176 Patents and other 114 (18) 96 Total identifiable intangibles $ 5,388 $ (848) $ 4,540 Leases The Company accounts for leases in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 842, Leases (“ASC Topic 842”), which the Company adopted under ASU No. 2016-02 “Leases (Topic 842)” effective January 1, 2019. The Company applied ASC Topic 842 to all leases existing at or commencing after January 1, 2019 and elected the package of transition practical expedients for expired or existing contracts, which does not require reassessment of: (1) whether any of our contracts are or contain leases, (2) lease classification and (3) initial direct costs. The Company also elected the practical expedient to adopt the new lease requirements through a cumulative effect adjustment in the period of adoption and did not adjust comparative periods. As a result of the adoption of ASC Topic 842 on January 1, 2019, the Company recorded operating right-of-use (“ROU”) assets of $8,503, operating lease liabilities of $9,016 and a cumulative effect adjustment to retained earnings for operating leases of $532. We determine if an arrangement is a lease at inception. The Company made the election to not apply the recognition requirements in ASC Topic 842 to short-term leases (i.e., leases of twelve months or less). Instead, the Company recognizes the lease payments in profit or loss on a straight-line basis over the lease term. Operating leases are included in operating lease ROU assets, current portion of operating lease liabilities, and operating lease liabilities, net of current in the Company’s condensed consolidated balance sheets. Finance leases are included in property and equipment, current portion of finance lease liabilities, and finance lease liabilities, net of current in the Company’s condensed consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. ROU assets and liabilities are recognized at the commencement date based on the present value of lease payments over the lease term. As most of the Company’s leases do not provide an implicit rate, we use our incremental borrowing rate in determining the present value of lease payments based on the information available at the commencement date. Our incremental borrowing rate reflects the estimated rate of interest that we would pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. We use the implicit rate when readily determinable. The ROU asset also includes any lease payments made and excludes lease incentives received. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term. Goodwill Goodwill represents the excess of the purchase price of a business over the estimated fair value of the identifiable assets acquired and liabilities assumed. As of September 30, 2019 and December 31, 2018, the Company reported $17,236 of goodwill related to the 2014 purchase of the silo manufacturing business from Loadcraft Industries Ltd. and the 2017 purchase of the assets of Railtronix. The Company evaluates goodwill for impairment annually, as of October 31, or more often as facts and circumstances warrant. Factors such as unexpected adverse economic conditions, competition and market changes may require more frequent assessments. There was no impairment for the three and nine months ended September 30, 2019 and 2018. Before employing detailed impairment testing methodologies, the Company may first evaluate the likelihood of impairment by considering qualitative factors relevant to the business, such as macroeconomic, industry, market or any other factors that have a significant bearing on fair value. If the Company first utilizes a qualitative approach and determines that it is more likely than not that goodwill is impaired, detailed testing methodologies are then applied. Otherwise, the Company concludes that no impairment has occurred. The Company may also choose to bypass a qualitative approach and opt instead to employ detailed testing methodologies, regardless of a possible more likely than not outcome. If the Company determines through the qualitative approach that detailed testing methodologies are required, or if the qualitative approach is bypassed, the Company compares the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Impairment of Long-Lived Assets and Definite-lived Intangible Assets Long-lived assets, such as property, plant, equipment and definite-lived intangible assets, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable, such as insufficient cash flows or plans to dispose of or sell long-lived assets before the end of their previously estimated useful lives. If the carrying amount is not recoverable, the Company recognizes an impairment loss equal to the amount by which the carrying amount exceeds fair value. The Company estimates fair value based on projected future discounted cash flows. Fair value calculations for long-lived assets and intangible assets contain uncertainties because it requires the Company to apply judgment and estimates concerning future cash flows, strategic plans, useful lives and market performance. The Company also applies judgment in the selection of a discount rate that reflects the risk inherent in the current business model. There was no impairment indicators for the three and nine months ended September 30, 2019 and 2018. Revenue Recognition In determining the appropriate amount of revenue to be recognized as we fulfill our obligations under the agreement, the following steps must be performed at contract inception: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations, including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) we satisfy each performance obligation. Revenues from system rental consist primarily of fixed monthly fees charged to customers for the use of our patented mobile proppant management systems that unload, store and deliver proppant and chemicals at oil and natural gas well sites, which is considered to be our performance obligation. Contracts with customers are typically on thirty- to sixty-day payment terms. Revenues are recognized over time as the performance obligations are satisfied under the terms of the customer contract. We determined that the performance obligation is satisfied over time as the customer simultaneously receives and consumes the benefits provided by the entity’s performance of services, typically as our systems are used by the customer. We measure progress using an input method based on resources consumed or expended relative to the total resources expected to be consumed or expended. We typically charge our customers for the rental of our systems on a monthly basis under agreements requiring the rental of a minimum number of systems for a period of twelve months. The Company is typically entitled to short fall payments if such minimum contractual obligations are not maintained by our customers. Minimum contractual obligations have been maintained and thus the Company has not recognized revenues related to shortfalls on such take or pay contractual obligations to date. Revenues from system services consist primarily of the fees charged to customers for services including mobilization and transportation of our systems, field supervision and support and services coordinating proppant delivery to systems, each of which are considered to be separate performance obligations. Contracts with customers are typically on thirty- to sixty-day payment terms. When the Company provides system services including field supervision and support, we determined that the performance obligation is satisfied over time as the customer simultaneously receives and consumes the benefits provided by the entity’s performance of the services, typically based on fixed weekly or monthly contractual rates for field supervision and support and when the Company provides services coordinating proppant delivery. We measure progress using an input method based on resources consumed or expended relative to the total resources expected to be consumed or expended. When the Company provides mobilization and transportation of our systems on behalf of our customers, we determined that the performance obligation is satisfied at a point in time when the system has reached its intended destination. Revenues from transloading services consist primarily of the fees charged to customers for transloading proppant at our transloading facility, which is considered to be our performance obligation. Transloading services operations commenced in January 2018. We provide rail-to-truck transloading and high-efficiency sand silo storage and transloading services at the facility. Contracts with customers are typically on thirty- to sixty-day payment terms. Revenues are typically recognized over time as the customer simultaneously receives and consumes the benefits provided by the entity’s performance of the transloading service based on a throughput fee per ton rate for proppant delivered to and transloaded at the facility. We measure progress based on the proppant delivered and transloaded at the facility. Under our agreements at the facility, quarterly minimum throughput volumes are required and the Company is entitled to short fall payments if such minimum quarterly contractual obligations are not maintained. These shortfalls are based on fixed minimum volumes at a fixed rate and are recognized over time as throughput volumes transloaded are below minimum throughput volumes required. The Company recorded $221 and $522 of shortfall revenue during the three and nine months ended September 30, 2019, respectively. Revenues from inventory software services consist primarily of the fees charged to customers for the use of our Railtronix inventory management software, which is considered to be our performance obligation. Revenues are recognized over time as the customer simultaneously receives and consumes the benefits provided by the entity’s performance based on a throughput fee to monitor proppant that is loaded into a railcar, stored at a transload facility or loaded into a truck. Deferred Revenue Deferred revenue consists of a $25,980 partial termination payment fee received in December 2018 in accordance with a contract modification which is accounted for prospectively. The partial termination payment fee represents the distinct unsatisfied portion of a contract to provide transloading services and are considered part of the transaction price and will be allocated to the remaining performance obligations under the contract. Deferred revenues in the condensed consolidated balance sheets were $15,950 and $25,458 as of September 30, 2019 and December 31, 2018, respectively, which will be recognized as revenue from transloading services. The Company recognized $3,203 and $9,508 of deferred revenue as revenue from transloading services in the condensed consolidated statements of operations for the three and nine months ended September 30, 2019, respectively. Refer to Note 13. “Subsequent Events” for termination information on this agreement and recognition of the remaining deferred revenue. No deferred revenue was recorded or recognized as revenue during the three and nine months ended September 30, 2018. Stock-based Compensation The Company accounts for its stock-based compensation including grants of restricted stock and options in the condensed consolidated statements of operations based on their fair values on the date of grant. The Company recognizes expense on a straight-line basis over the awards’ vesting period, which is generally the requisite service period. Research and Development The Company expenses research and development costs as incurred, which is included in selling, general and administrative expenses in the condensed consolidated statements of operations. There were no research and development costs for the three and nine months ended September 30, 2019 and 2018. Financial Instruments The carrying value of the Company’s financial instruments, consisting of cash, accounts receivable, notes receivable, accounts payable and insurance premium financing, approximates their fair value due to the short maturity of such instruments. Financial instruments also consist of a revolving credit facility and term loans, for which fair value approximates carrying value as the debt bears interest at a variable rate which is reflective of current rates otherwise available to the Company. As of September 30, 2019, we had no borrowings under the 2019 Credit Agreement (as defined below) outstanding. Unless otherwise noted, it is management’s opinion that the Company is not exposed to significant interest, currency or credit risks arising from these financial instruments. Fair Value Measurements The Company’s financial assets and liabilities are to be measured using inputs from the three levels of the fair value hierarchy, of which the first two are considered observable and the last unobservable, which are as follows: · Level 1—Inputs are unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date; · Level 2—Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active or other inputs corroborated by observable market data for substantially the full term of the assets or liabilities; and · Level 3—Unobservable inputs that reflect the Company’s assumptions that market participants would use in pricing assets or liabilities based on the best information available. Income Taxes Solaris Inc. is a corporation and, as a result, is subject to United States federal, state and local income taxes. For the three months ended September 30, 2019 and 2018, we recognized a combined United States federal and state provision for income taxes of $3,703 and $4,237, respectively. For the nine months ended September 30, 2019 and 2018, we recognized a combined United States federal and state provision for income taxes of $12,042 and $9,541, respectively. Solaris LLC is treated as a partnership for United States federal income tax purposes and therefore does not pay United States federal income tax on its taxable income. Instead, the Solaris LLC members are liable for United States federal income tax on their respective shares of the Company’s taxable income reported on the members’ United States federal income tax returns. Our revenues are derived through transactions in several states, which may be subject to state and local taxes. Accordingly, we have recorded a liability for state and local taxes that management believes is adequate for activities as of September 30, 2019 and December 31, 2018. We account for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events included in the condensed consolidated financial statements. Under this method, we determine deferred tax assets and liabilities on the basis of the differences between the book value and tax bases of assets and liabilities by using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period in which the enactment date occurs. We recognize deferred tax assets to the extent we believe these assets are more-likely-than-not to be realized. In making such a determination, we consider all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax planning strategies and recent results of operations. We record uncertain tax positions on the basis of a two-step process in which (1) we determine whether it is more-likely-than-not the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions meeting the more-likely-than-not recognition threshold, we recognize the largest amount of tax benefit that is more than 50% likely to be realized upon ultimate settlement with the related tax authority. Interest and penalties related to income taxes are included in the benefit (provision) for income taxes in our condensed consolidated statement of operations. We have not incurred any significant interest or penalties related to income taxes in any of the periods presented. See Note 9. “Income Taxes” for additional information regarding income taxes. Payable Related to the Tax Receivable Agreement In connection with the Solaris Inc.’s initial public offering (the “IPO” or the “Offering”), Solaris Inc. entered into a Tax Receivable Agreement (the “Tax Receivable Agreement”) with the members of Solaris LLC immediately prior to the IPO (each such person and any permitted transferee, a “TRA Holder,” and together, the “TRA Holders”) on May 17, 2017. This agreement generally provides for the payment by Solaris Inc. to each TRA Holder of 85% of the net cash savings, if any, in United States federal, state and local income tax and franchise tax that Solaris Inc. actually realizes (computed using simplifying assumptions to address the impact of state and local taxes) or is deemed to realize in certain circumstances in periods after the IPO as a result of (i) certain increases in tax basis that occur as a result of Solaris Inc.’s acquisition (or deemed acquisition for United States federal income tax purposes) of all or a portion of such TRA Holder’s Solaris LLC Units in connection with the IPO or pursuant to the exercise of the Redemption Right or the Call Right (each as defined in Solaris LLC’s Second Amended and Restated Limited Liability Company Agreement (the “Solaris LLC Agreement”)) and (ii) imputed interest deemed to be paid by Solaris Inc. as a result of, and additional tax basis arising from, any payments Solaris makes under the Tax Receivable Agreement. Solaris Inc. will retain the benefit of the remaining 15% of these cash savings. As of September 30, 2019 and December 31, 2018, Solaris Inc. recorded a payable related to the Tax Receivable Agreement of $67,987 and $56,149, respectively. The increase in payables related to the Tax Receivable Agreement is a result of Solaris Inc.’s acquisition (or deemed acquisition for United States federal income tax purposes) of Solaris LLC Units from TRA Holders during the nine months ended September 30, 2019. Environmental Matters The Company is subject to various federal, state and local laws and regulations relating to the protection of the environment. Management has established procedures for the ongoing evaluation of the Company’s operations, to identify potential environmental exposures and to comply with regulatory policies and procedures. Environmental expenditures that relate to current operations are expensed or capitalized as appropriate. Expenditures that relate to an existing condition caused by past operations and do not contribute to current or future revenue generation are expensed as incurred. Liabilities are recorded when environmental costs are probable, and the costs can be reasonably estimated. The Company maintains insurance which may cover in whole or in part certain environmental expenditures. As of September 30, 2019 and December 31, 2018, there were no environmental matters deemed probable. Segment Information Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, or decision-making group, in making decisions on how to allocate resources and assess performance. The Company’s chief operating decision maker is the Chief Executive Officer. The Company and the Chief Executive Officer view the Company’s operations and manage its business as one operating segment. All long-lived assets of the Company reside in the United States. Accounting Standards Recently Issued But Not Yet Adopted There are no accounting standards recently issued, but not yet adopted which are expected to impact our condensed consolidated financial statements.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	9 Months Ended
	Sep. 30, 2019
Prepaid Expenses and Other Current Assets.
Prepaid Expenses and Other Current Assets	3. Prepaid Expenses and Other Current Assets Prepaid expenses and other currents assets were comprised of the following at September 30, 2019 and December 31, 2018: September 30, December 31, 2019 2018 Prepaid purchase orders $ 1,106 $ 2,802 Prepaid insurance 1,481 576 Deposits 901 882 Incentive receivables and other assets 1,758 1,232 Prepaid expenses and other current assets $ 5,246 $ 5,492

Property, Plant and Equipment

Property, Plant and Equipment	9 Months Ended
	Sep. 30, 2019
Property, Plant and Equipment.
Property, Plant and Equipment	4. Property, Plant and Equipment Property, plant and equipment was comprised of the following at September 30, 2019 and December 31, 2018: September 30, December 31, 2019 2018 Systems and related equipment $ 287,565 $ 258,600 Systems in process 16,437 11,245 Transloading facility and equipment 40,254 40,218 Computer hardware and software 1,238 1,185 Machinery and equipment 5,216 5,126 Vehicles 8,044 8,334 Buildings 4,339 4,280 Land 612 612 Furniture and fixtures 284 282 Property, plant and equipment, gross 363,989 329,882 Less: accumulated depreciation (52,736) (33,344) Property, plant and equipment, net $ 311,253 $ 296,538 Depreciation expense for the three months ended September 30, 2019 and 2018 was $6,713 and $5,133, respectively, of which $5,773 and $4,133 is attributable to cost of system rental, $384 and $347 is attributable to cost of system services, $411 and $529 is attributable to cost of transloading services and $145 and $124 is attributable to selling, general and administrative expenses, respectively. Depreciation expense for the nine months ended September 30, 2019 and 2018 was $19,291 and $11,908, respectively, of which $16,481 and $10,128 is attributable to cost of system rental, $1,173 and $889 is attributable to cost of system services, $1,231 and $544 is attributable to cost of transloading services and $406 and $347 is attributable to selling, general and administrative expenses, respectively. The Company capitalized $187 and $182 of depreciation expense associated with machinery and equipment used in the manufacturing of its systems for the three months ended September 30, 2019 and 2018, respectively. The Company capitalized $559 and $501 of depreciation expense associated with machinery and equipment used in the manufacturing of its systems for the nine months ended September 30, 2019 and 2018, respectively.

Accrued Liabilities

Accrued Liabilities	9 Months Ended
	Sep. 30, 2019
Accrued Liabilities
Accrued Liabilities	5. Accrued Liabilities Accrued liabilities were comprised of the following at September 30, 2019 and December 31, 2018: September 30, December 31, 2019 2018 Property, plant and equipment $ 194 $ 2,153 Employee related expenses 3,996 4,500 Selling, general and administrative 1,491 944 Cost of revenue 5,700 2,702 Excise, franchise and sales taxes 4,045 1,461 Ad valorem taxes 1,306 774 Other 102 124 Accrued liabilities $ 16,834 $ 12,658

Leases

Leases	9 Months Ended
	Sep. 30, 2019
Leases
Leases	6. Leases The Company leases land and equipment under operating leases which expire at various dates through February 2047. These land leases include commitments related to a 30-year land lease with the State of Oklahoma related to the Company’s Kingfisher Facility. Equipment leases include locomotives rented from third-parties in order to facilitate rail transloading activities at the Kingfisher Facility. Upon completion of the primary term, both parties have substantive rights to terminate the leases. As a result, enforceable rights and obligations do not exist under the rental agreements subsequent to the primary term. Additionally, the Company leases office and storage from third parties for our corporate and field locations under operating leases, which include commitments related to a guarantee of lease agreement with Solaris Energy Management, LLC, a related party of the Company, related to the rental of office space for the Company's corporate headquarters. Refer to Note 12. “Related Party Transactions” for additional information regarding related party transactions recognized. Upon completion of the primary term, both parties have substantive rights to terminate the leases. As a result, enforceable rights and obligations do not exist under the rental agreements subsequent to the primary term. Solaris LLC leases property from the City of Early, Texas under an agreement classified as a finance lease. The lease expires on February 25, 2025. The finance lease obligation is payable in monthly installments including imputed interest. The Company also leases certain office equipment with purchase options upon the end of lease terms which are accounted for as finance leases with various expiration dates. As of September 30, 2019 and December 31, 2018, the Company had property, plant and equipment under finance leases with a cost of $299 and accumulated depreciation of $101 and $85, respectively. The Company’s lease agreements do not include both lease and non-lease components, extension options or residual value guarantees, and there are no leases that have yet to commence. Additionally, our lease agreements do not impose restrictions on our ability to pay dividends or incur financing obligations. The components of lease expense were as follows: Three Months Ended Nine Months Ended September 30, 2019 September 30, 2019 Operating lease cost (1) (2) $ 297 $ 890 Finance lease cost Amortization of ROU assets 8 25 Interest on lease liabilities 1 1 Total finance lease cost $ 9 $ 26 (1) Includes short term leases. (2) Operating lease costs of $185, $20 and $92 were reported in Selling, general and administrative, Cost of system services and Cost of transloading services for the three months ended September 30, 2019, respectively. Operating lease costs of $556, $58 and $276 were reported in Selling, general and administrative, Cost of system services and Cost of transloading services for the nine months ended September 30, 2019, respectively. No variable lease costs were recognized during the three and nine months ended September 30, 2019. Future minimum lease payments under non-cancellable operating leases as of December 31, 2018 were as follows: Year Ending December 31, Amount 2019 $ 1,432 2020 1,375 2021 1,299 2022 1,093 2023 1,092 Thereafter 9,725 Total minimum lease payments $ 16,016 Future minimum lease payments under non-cancellable leases as of September 30, 2019 were as follows: Year Ending December 31, Operating Leases Finance Leases 2019 (remainder of) $ 243 14 2020 1,116 35 2021 1,060 33 2022 1,091 33 2023 1,100 33 Thereafter 9,463 36 Total future minimum lease payments 14,073 184 Less: effects of discounting (5,514) (17) Total lease liabilities $ 8,559 $ 167 Supplemental cash flow information related to leases was as follows: Three Months Ended Nine Months Ended September 30, 2019 September 30, 2019 Supplemental Cash Flows Information Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 243 $ 877 Financing cash flows from finance leases 9 26 Other information related to leases was as follows: September 30, 2019 Weighted Average Remaining Lease Term Operating leases 13.9 years Finance leases 5.4 years Weighted Average Discount Rate Operating leases Finance leases

Senior Secured Credit Facility

Senior Secured Credit Facility	9 Months Ended
	Sep. 30, 2019
Senior Secured Credit Facility
Senior Secured Credit Facility	7. Senior Secured Credit Facility On April 26, 2019, Solaris LLC entered into an Amended and Restated Credit Agreement (the “2019 Credit Agreement”) by and among Solaris LLC, as borrower, each of the lenders party thereto and Wells Fargo Bank, National Association, as administrative agent. The 2019 Credit Agreement replaced, in its entirety, Solaris LLC’s 2018 Credit Agreement (as defined herein). The 2019 Credit Agreement consists of an initial $50,000 revolving loan commitment (the “Loan”) with a $25,000 uncommitted accordion option to increase the Loan availability to $75,000. The term of the 2019 Credit Agreement expires on April 26, 2022. Our obligations under the Loan are generally secured by a pledge of substantially all the assets of Solaris LLC and its subsidiaries, and such obligations are guaranteed by Solaris LLC’s domestic subsidiaries other than Immaterial Subsidiaries (as defined in the 2019 Credit Agreement). We have the option to prepay the loans at any time without penalty. Borrowings under the 2019 Credit Agreement bear interest at either LIBOR or an alternate base rate plus an applicable margin, and interest is payable quarterly. The applicable margin ranges from 1.75% to 2.50% for Eurodollar loans and 0.75% to 1.50% for alternate base rate loans, in each case depending on our total leverage ratio. The 2019 Credit Agreement requires that we pay a quarterly commitment fee on undrawn amounts of the Loan, ranging from 0.25% to 0.375% depending upon the total leverage ratio. The 2019 Credit Agreement requires that we maintain ratios of (a) consolidated EBITDA to interest expense of not less than 2.75 to 1.00, (b) senior indebtedness to consolidated EBITDA of not more than 2.50 to 1.00 and (c) the sum of 100% of eligible accounts, inventory and fixed assets to the total revolving exposure of not less than 1.00 to 1.00 when the total leverage ratio is greater than 2.00 to 1.00 and total revolving exposure under the Loan exceeds $3,000. For the purpose of these tests, certain items are subtracted from indebtedness and senior indebtedness. EBITDA, as defined in the 2019 Credit Agreement, excludes certain noncash items and any extraordinary, unusual or non-recurring gains, losses or expenses. The 2019 Credit Agreement also requires that we prepay any outstanding borrowings under the Loan in the event our total leverage ratio is greater than 1.00 to 1.00 and our consolidated cash balance exceeds $20,000, taking into account certain adjustments. Capital expenditures are not restricted unless borrowings under the Loan exceed $5,000 for any 180 consecutive day period, in which case capital expenditures will be permitted up to $100,000 plus any unused availability for capital expenditures from the immediately preceding fiscal year. As of September 30, 2019, we had no borrowings under the 2019 Credit Agreement outstanding and ability to draw $50,000. As of September 30, 2019 we were in compliance will all covenants in accordance with the 2019 Credit Agreement. On January 19, 2018, Solaris LLC entered into a credit agreement (the “2018 Credit Agreement”) which consisted of a $50,000 advancing term loan (the “Advance Loan”) and a $20,000 revolving loan, with a $10,000 uncommitted accordion option to increase the total revolving loans (the “Revolving Loan”, and together with the Advance Loan, the “Loans”). The 2019 Credit Agreement replaced, in its entirety, the 2018 Credit Agreement. As of December 31, 2018 we had $13,000 of borrowings outstanding under the 2018 Credit Agreement. During the three and nine months ended September 30, 2019, all outstanding borrowings were repaid and as of September 30, 2019. Borrowings under the 2018 Credit Agreement bore interest at one-month LIBOR plus an applicable margin and interest were payable monthly. The applicable margin ranged from 3.00% to 3.50% depending on our senior leverage ratio. Borrowings under the Revolving Loan had a weighted average interest rate of 5.49% for the nine months ended September 30, 2019. The 2018 Credit Agreement required that we pay a monthly commitment fee on undrawn amounts of the Revolving Loan, ranging from 0.25% to 0.50% depending upon the average outstanding balance of the obligations relative to the Revolving Loan commitments.

Equity

Equity	9 Months Ended
	Sep. 30, 2019
Equity
Equity	8. Equity On September 26, 2019, Solaris Inc. paid a quarterly cash dividend of $0.10 per share of Class A common stock. Solaris LLC paid a distribution of $4,759, or $0.10 per Solaris LLC Unit, to all Solaris LLC unitholders as of September 19, 2019, $3,165 of which was paid to Solaris Inc. Solaris Inc. used the proceeds from the distribution to pay the dividend to all holders of shares of Class A common stock as of September 19, 2019, which totaled $3,165, including $64 related to shares of restricted stock. On June 26, 2019, Solaris Inc. paid a quarterly cash dividend of $0.10 per share of Class A common stock. Solaris LLC paid a distribution of $4,758, or $0.10 per Solaris LLC Unit, to all Solaris LLC unitholders as of June 14, 2019, $3,164 of which was paid to Solaris Inc. Solaris Inc. used the proceeds from the distribution to pay the dividend to all holders of shares of Class A common stock as of June 14, 2019, which totaled $3,164, including $74 related to shares of restricted stock. On March 29, 2019, Solaris Inc. paid a quarterly cash dividend of $0.10 per share of Class A common stock. Solaris LLC paid a distribution of $4,757, or $0.10 per Solaris LLC Unit, to all Solaris LLC unitholders as of March 22, 2019, $3,119 of which was paid to Solaris Inc. Solaris Inc. used the proceeds from the distribution to pay the dividend to all holders of shares of Class A common stock as of March 22, 2019, which totaled $3,119, including $79 related to shares of restricted stock. Stock-based compensation The Company’s long-term incentive plan for employees, directors and consultants of the Company and its affiliates (the “LTIP”) provides for the grant of all or any of the following types of equity-based awards: (1) incentive stock options qualified as such under United States federal income tax laws; (2) stock options that do not qualify as incentive stock options; (3) stock appreciation rights; (4) restricted stock awards; (5) restricted stock units; (6) bonus stock; (7) performance awards; (8) dividend equivalents; (9) other stock-based awards; (10) cash awards; and (11) substitute awards. Subject to adjustment in accordance with the terms of the LTIP, 5,118,080 shares of Solaris Inc.’s Class A common stock have been reserved for issuance pursuant to awards under the LTIP. Class A common stock withheld to satisfy exercise prices or tax withholding obligations will be available for delivery pursuant to other awards. The LTIP will be administered by the Board, the Compensation Committee of the Board or an alternative committee appointed by the Board. A total of 591,261 options to purchase Class A common stock of the Company have been issued to employees, directors and consultants under the LTIP at an exercise price of $2.87 per option and a weighted average grant date fair value of $12.04 per option. All options were vested by November 13, 2017. As of September 30, 2019, 522,285 options have been exercised, 33,348 forfeited and 35,628 remain outstanding. The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model. Expected volatility is based on implied volatilities from historical trading of publicly traded companies which are in the same industry sector. The simplified method is used to derive an expected term. The expected term represents an estimate of the time options are expected to remain outstanding. The risk-free rate for periods within the contractual life of the option is based on the United States treasury yield curve in effect at the time of grant. Compensation cost, as measured at the grant date fair value of the award, is recognized as an expense over the employee’s requisite service period for service-based awards (generally the vesting period of the award of four years). For the three and nine months ended September 30, 2019 and 2018, the Company did not recognize stock-based compensation expense on options. The Company accounts for its stock-based compensation including grants of restricted stock in the condensed consolidated statements of operations based on their estimated fair values on the date of grant. The following table further summarizes activity related to restricted stock for the three and nine months ended September 30, 2019 and 2018: Restricted Stock Awards 2019 2018 Unvested at January 1, 411,497 1,218,265 Awarded 375,068 2,120 Vested (706) — Forfeited (405) (848) Unvested at March 31, 785,454 1,219,537 Awarded 29,847 — Vested (67,674) (345,520) Forfeited (7,896) (21,495) Unvested at June 30, 739,731 852,522 Awarded 43,830 86,544 Vested (138,821) (297,371) Forfeited (9,644) (223,988) Unvested at September 30, 635,096 417,707 For the three months ended September 30, 2019, the Company recognized $10, $71, $5 and $1,139 of stock-based compensation expense on restricted stock in cost of system rental, cost of system services, cost of transloading services and selling, general and administrative, respectively, in the condensed consolidated statements of operations and $37 within property, plant and equipment, net in the condensed consolidated balance sheets. For the nine months ended September 30, 2019, the Company recognized $24, $187, $12 and $3,042 of stock-based compensation expense on restricted stock in cost of system rental, cost of system services, cost of transloading services and selling, general and administrative, respectively, in the condensed consolidated statements of operations and $133 within property, plant and equipment, net in the condensed consolidated balance sheets. Compensation expense includes adjustment for forfeitures as incurred. As of September 30, 2019, 635,096 shares of restricted stock are issued and are outstanding. 1,497 shares, 350,907 shares, 149,688 shares and 133,004 shares of restricted stock vest in 2019, 2020, 2021 and 2022, respectively. Earnings Per Share Basic earnings per share of Class A common stock is computed by dividing net income attributable to Solaris by the weighted-average number of shares of Class A common stock outstanding during the same period. Diluted earnings per share is computed giving effect to all potentially dilutive shares. The following table sets forth the calculation of earnings per share, or EPS, for the three and nine months ended September 30, 2019 and 2018: Three Months Ended September 30, Nine Months Ended September 30, Basic net income per share: 2019 2018 2019 2018 Numerator Net income attributable to Solaris $ 11,398 $ 13,019 $ 36,991 $ 29,546 Less income attributable to participating securities (1) (245) (251) (817) (1,042) Net income attributable to common stockholders $ 11,153 $ 12,768 $ 36,174 $ 28,504 Denominator Weighted average number of unrestricted outstanding common shares used to calculate basic net income per share 30,951 26,197 27,270 25,216 Effect of dilutive securities: Stock options 29 132 47 164 Diluted weighted-average shares of Class A common stock outstanding used to calculate diluted net income per share 30,980 26,329 27,317 25,380 Earnings per share of Class A common stock - basic $ 0.36 0.49 1.33 1.13 Earnings per share of Class A common stock - diluted $ 0.36 0.49 1.33 1.12 (1) The Company’s restricted shares of common stock are participating securities. The following number of weighted-average potentially dilutive shares were excluded from the calculation of diluted earnings per share because the effect of including such potentially dilutive shares would have been antidilutive upon conversion: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Class B common stock 15,939 20,398 15,598 21,085 Restricted stock awards 129 195 242 524 Total 16,068 20,593 15,840 21,609

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2019
Income Taxes
Income Taxes	9. Income Taxes Income Taxes Solaris Inc. is a corporation and, as a result is subject to United States federal, state and local income taxes. Solaris LLC is treated as a pass-through entity for United States federal tax purposes and in most state and local jurisdictions. As such, Solaris LLC’s members, including the Solaris Inc., are liable for federal and state income taxes on their respective shares of Solaris LLC’s taxable income. Solaris LLC is liable for income taxes in those states not recognizing its pass-through status. The effective combined United States federal and state income tax rates were 14.80% and 13.98% for the three months ended September 30, 2019 and 2018, respectively. The effective combined United States federal and state income tax rates were 14.88% and 13.54% for the nine months ended September 30, 2019 and 2018, respectively. For the three and nine months ended September 30, 2019 and 2018, our effective tax rate differed from the statutory rate primarily due to Solaris LLC’s pass-through treatment for United States federal income tax purposes. The Company’s deferred tax position reflects the net tax effects of the temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax reporting. The largest components of the Company’s deferred tax position relate to the Company’s investment in Solaris LLC and net operating loss carryovers. The Company recorded a deferred tax asset and additional paid-in capital for the difference between the book value and the tax basis of the Company’s investment in Solaris LLC. This difference originates from the equity offerings of Class A common stock, exchanges of membership interest in Solaris LLC (together with a corresponding number of shares of Class B common stock) for shares of Class A common stock, and a contribution of Class A common stock in connection with stock-based compensation. Based on our cumulative earnings history and forecasted future sources of taxable income, we believe that we will be able to realize our deferred tax assets in the future. As the Company reassesses these assumptions in the future, changes in forecasted taxable income may alter this expectation and may result in an increase in to the valuation allowance and an increase in the effective tax rate. The Company evaluates its tax positions and recognizes only tax benefits that, more likely than not, will be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The tax position is measured at the largest amount of benefit that has a greater than 50.0% likelihood of being realized upon settlement. As of September 30, 2019 and December 31, 2018, the Company’s uncertain tax benefits totaling $816 are reported as a component of the net deferred tax asset in the condensed consolidated balance sheets. The full balance of unrecognized tax benefits as of September 30, 2019, if recognized, would affect the effective tax rate. However, we do not believe that any of the unrecognized tax benefits will be realized within the coming year. The Company has elected to recognize interest and penalties related to unrecognized tax benefits in income tax expense notwithstanding the fact that, as of September 30, 2019, the Company has not accrued any penalties or interest. Payables Related to the Tax Receivable Agreement As of September 30, 2019, our liability under the Tax Receivable Agreement was $67,987, representing 85% of the calculated net cash savings in United States federal, state and local income tax and franchise tax that Solaris Inc. anticipates realizing in future years from certain increases in tax basis and certain tax benefits attributable to imputed interest as a result of Solaris Inc.’s acquisition (or deemed acquisition for United States federal income tax purposes) of Solaris LLC Units in connection with the IPO or pursuant to an exercise of the Redemption Right or the Call Right (each as defined in the Solaris LLC Agreement). The projection of future taxable income involves significant judgment. Actual taxable income may differ from our estimates, which could significantly impact our liability under the Tax Receivable Agreement. We have determined it is more-likely-than-not that we will be able to utilize all of our deferred tax assets subject to the Tax Receivable Agreement; therefore, we have recorded a liability under the Tax Receivable Agreement related to the tax savings we may realize from certain increases in tax basis and certain tax benefits attributable to imputed interest as a result of Solaris Inc.’s acquisition (or deemed acquisition for United States federal income tax purposes) of Solaris LLC Units in connection with the IPO or pursuant to an exercise of the Redemption Right or the Call Right (each as defined in the Solaris LLC Agreement). If we determine the utilization of these deferred tax assets is not more-likely-than-not in the future, our estimate of amounts to be paid under the Tax Receivable Agreement would be reduced. In this scenario, the reduction of the liability under the Tax Receivable Agreement would result in a benefit to our condensed consolidated statement of operations.

Concentrations

Concentrations	9 Months Ended
	Sep. 30, 2019
Concentrations
Concentrations	10. Concentrations For the three months ended September 30, 2019, two customers accounted for 14% and 12% of the Company’s revenue. For the three months ended September 30, 2018, two customers accounted for 13%, and 10% of the Company’s revenue. For the nine months ended September 30, 2019, four customers accounted for 14%, 11%, 11% and 10% of the Company’s revenue. For the nine months ended September 30, 2018, three customers accounted for 16%, 10% and 10% of the Company’s revenue. As of September 30, 2019, four customers accounted for 14%, 14%, 12% and 10% of the Company’s accounts receivable. As of December 31, 2018, three customers accounted for 20%, 10% and 10% of the Company’s accounts receivable. For the three months ended September 30, 2019, one supplier accounted for 38% of the Company’s total purchases. For the three months ended September 30, 2018, two suppliers accounted for 17% and 12% of the Company’s total purchases. For the nine months ended September 30, 2019, one supplier accounted for 17% of the Company’s total purchases. For the nine months ended September 30, 2018, two suppliers accounted for 14% and 12% of the Company’s total purchases. As of September 30, 2019, one supplier accounted for 77% of the Company’s accounts payable. As of December 31, 2018, one supplier accounted for 13% of the Company’s accounts payable.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies
Commitments and Contingencies	11. Commitments and Contingencies In the normal course of business, the Company is subjected to various claims, legal actions, contract negotiations and disputes. The Company provides for losses, if any, in the year in which they can be reasonably estimated. In management’s opinion, there are currently no such matters outstanding that would have a material effect on the accompanying condensed consolidated financial statements. The table below provides estimates of the timing of future payments that we are contractually obligated to make based on agreements in place at September 30, 2019: For the Year Ending December 31, 2019 2020 2021 2022 2023 Thereafter Total (in thousands) Operating lease obligations (1) $ 243 $ 1,116 $ 1,060 $ 1,091 $ 1,100 $ 9,463 $ 14,073 Finance lease obligations (2) 14 35 33 33 33 36 184 Commitment fees on Revolving Loan (3) 32 125 125 40 — — 322 Purchase commitments (4) — 2,588 2,217 — — — 4,805 Other commitments 32 274 255 37 2 — 600 Total $ 321 $ 4,138 $ 3,690 $ 1,201 $ 1,135 $ 9,499 19,984 (1) (2) (3) (4) Other Commitments In the normal course of business, the Company has certain short-term purchase obligations and commitments for products and services, primarily related to purchases of materials used in the manufacturing of its systems. As of September 30, 2019 and December 31, 2018, the Company had commitments of approximately $4,805 and $18,998, respectively, related to these commitments. In connection with the acquisition of Railtronix, the seller is entitled to certain performance-based cash awards totaling $2,500 upon the achievement of certain financial milestones. As of September 30, 2019, one milestone had been achieved and the Company paid and recognized $1,625 in June 2018 in other operating expense in the condensed consolidated statements of operations. However, as of September 30, 2019, the Company had not concluded that the remaining milestone will be achieved and thus has not recognized additional obligations in the condensed consolidated financial statements. The Company has executed a guarantee of lease agreement with Solaris Energy Management, LLC, a related party of the Company, related to the rental of office space for the Company’s corporate headquarters. The total future guaranty under the guarantee of lease agreement with Solaris Energy Management, LLC is $9,477 as of September 30, 2019. Refer to Note 12. “Related Party Transactions” for additional information regarding related party transactions recognized and Note 6. “Leases” for operating lease discussion.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2019
Related Party Transactions
Related Party Transactions	12. Related Party Transactions The Company recognizes certain costs incurred in relation to transactions with entities owned or partially owned by William A. Zartler, the Chief Executive Officer and Chairman of the Board. The costs incurred in connection with these services include rent paid for office space, travel services, personnel, consulting and administrative costs. For the three months ended September 30, 2019 and 2018, Solaris LLC paid $217 and $164, respectively, for these services. For the nine months ended September 30, 2019 and 2018, Solaris LLC paid $836 and $503, respectively, for these services. As of September 30, 2019 and December 31, 2018, the Company included $231 and $232, respectively, in prepaid expenses and other current assets on the condensed consolidated balance sheets. As of September 30, 2019 and December 31, 2018, the Company included $78 and $103, respectively, of accruals to related parties in accrued liabilities on the condensed consolidated balance sheets. These costs are primarily incurred in connection with the amended and restated administrative services agreement, dated May 17, 2017, between Solaris LLC and Solaris Energy Management, LLC, a company partially owned by William A. Zartler. Payables Related to the Tax Receivable Agreement In connection with the IPO, Solaris Inc. entered into the Tax Receivable Agreement with the TRA Holders on May 17, 2017. See Note 9. “Income Taxes” for further discussion of the impact of the Tax Receivable Agreement on Solaris Inc.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2019
Subsequent Events
Subsequent Events	13. Subsequent Events Kingfisher Facility The Company has received notice from the customer party to the Company’s agreement for sand storage and transloading at the Company’s Kingfisher Facility that the customer intends to terminate the agreement effective December 31, 2019. The remaining term of the agreement will provide for replacement volumes by which the transloading activity of a third party during the fourth quarter of 2019 can be used to offset existing minimum contracted volumes related to the agreement. The agreement was previously partially terminated in December 2018, at which point the Company received a $25,980 partial termination fee. As of September 30, 2019, $15,950 of the partial termination fee is reported as deferred revenue in the Company’s Condensed Consolidated Balance Sheets. The Company anticipates being paid $1,680 in 2020 after termination of the agreement. Assuming termination occurs during the fourth quarter of 2019, deferred revenue of $17,630 will be recognized over the term of the remaining performance obligations of the Company, which would conclude on December 31, 2019. The Company is currently engaged in discussions with potential customers regarding utilization of capacity at the Kingfisher Facility. The Company will continue to assess the carrying values of the assets at the Kingfisher Facility and if circumstances lead the Company to believe they may not be recoverable, the Company may incur an impairment charge in the future.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2019
Summary of Significant Accounting Policies
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The accompanying interim unaudited condensed consolidated financial statements of Solaris Inc. have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). These financial statements reflect all normal recurring adjustments that are necessary for fair presentation. Operating results for the three and nine months ended September 30, 2019 and 2018 are not necessarily indicative of the results that may be expected for the full year or for any interim period. The unaudited interim condensed consolidated financial statements should be read in conjunction with Solaris Inc.’s Annual Report on Form 10-K/A for the year ended December 31, 2018. Solaris Oilfield Infrastructure, Inc. (either individually or together with its subsidiaries, as the context requires, “Solaris Inc.” or the “Company”) is the managing member of Solaris Oilfield Infrastructure, LLC (“Solaris LLC”) and is responsible for all operational, management and administrative decisions relating to Solaris LLC's business. Solaris Inc. consolidates the financial results of Solaris LLC and its subsidiaries and reports non-controlling interest related to the portion of the units in Solaris LLC (the “Solaris LLC Units”) not owned by Solaris Inc., which will reduce net income attributable to the holders of Solaris Inc.’s Class A common stock All material intercompany transactions and balances have been eliminated upon consolidation.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Significant estimates used in the preparation of these condensed consolidated financial statements include, but are not limited to, stock-based compensation, depreciation associated with property, plant and equipment and related impairment considerations of those assets, determination of fair value of intangible assets acquired in business combinations, determination of the present value of lease payments and right-of-use assets and certain other assets and liabilities. Actual results could differ from management’s best estimates as additional information or actual results become available in the future, and those differences could be material.
Cash	Cash For the purposes of the statements of cash flows, the Company considers all short-term, highly liquid, investments with an original maturity of three months or less to be cash equivalents. Cash is deposited in demand accounts in federally insured domestic institutions to minimize risk. Accounts of each institution are insured by Federal Deposit Insurance Corporation. Cash balances at times may exceed federally-insured limits. We have not incurred losses related to these deposits.
Accounts Receivable	Accounts Receivable Accounts receivable consists of trade receivables recorded at the invoice amount, plus accrued revenue that is not yet billed, less an estimated allowance for doubtful accounts (if any). Accounts receivable are generally due within 60 days or less, or in accordance with terms agreed with customers. The Company considers accounts outstanding longer than the payment terms past due. The Company determines the allowance by considering a number of factors, including the length of time trade accounts receivable are past due, previous loss history, the customer’s current ability to pay its obligation, and the condition of the general economy and the industry as a whole. Accounts receivable are written off when they are deemed uncollectible, and payments subsequently received on such receivables are credited to the allowance for doubtful accounts. Allowance for doubtful accounts was zero as of September 30, 2019 and December 31, 2018.
Inventories	Inventories Inventories consist of materials used in the manufacturing of the Company’s systems, which include raw materials and purchased parts and is stated at the lower of cost or net realizable value. Net realizable value is determined, giving consideration to quality, excessive levels, obsolescence and other factors. Adjustments that reduce stated amounts will be recognized as impairments in the condensed consolidated statements of operations. There were no impairments recorded for the three and nine months ended September 30, 2019 and 2018.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at cost, or fair value for assets acquired in a business combination, less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful service lives of the assets as noted below: Useful Life Systems and related equipment Up to 15 years Machinery and equipment 3-10 years Furniture and fixtures 5 years Computer hardware and software 3-10 years Vehicles 5 years Transloading facility and equipment 15-30 years Buildings and leasehold improvements 15 years Systems that are in the process of being manufactured are considered property, plant and equipment. However, the systems do not depreciate until they are fully completed. Systems in process are a culmination of material, labor and overhead. Expenditures for maintenance and repairs are charged against income as incurred. Betterments that increase the value or materially extend the life of the related assets are capitalized. Upon sale or disposition of property and equipment, the cost and related accumulated depreciation and amortization are removed from the condensed consolidated financial statements and any resulting gain or loss is recognized in the condensed consolidated statements of operations.
Definite-lived Intangible Assets	Definite-lived Intangible Assets Identified intangible assets with determinable lives consist primarily of customer relationships, a non-competition agreement and software acquired in the acquisition of Railtronix, LLC (“Railtronix”), as well as patents that were filed for our systems and other intellectual property. Amortization on these assets is calculated on the straight-line method over the estimated useful lives of the assets, which is five to fifteen years. The Company recorded amortization expense of $195 for each of the three months ended September 30, 2019 and 2018. The Company recorded amortization expense of $584 and $606 for the nine months ended September 30, 2019 and 2018, respectively. Identified intangible assets by major classification consist of the following: Accumulated Net Book Gross Amortization Value As of September 30, 2019: Customer relationships $ 4,703 $ (1,232) $ 3,471 Software acquired in the acquisition of Railtronix 346 (91) 255 Non-competition agreement 225 (82) 143 Patents and other 114 (27) 87 Total identifiable intangibles $ 5,388 $ (1,432) $ 3,956 As of December 31, 2018: Customer relationships $ 4,703 $ (727) $ 3,976 Software acquired in the acquisition of Railtronix 346 (54) 292 Non-competition agreement 225 (49) 176 Patents and other 114 (18) 96 Total identifiable intangibles $ 5,388 $ (848) $ 4,540
Leases	Leases The Company accounts for leases in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 842, Leases (“ASC Topic 842”), which the Company adopted under ASU No. 2016-02 “Leases (Topic 842)” effective January 1, 2019. The Company applied ASC Topic 842 to all leases existing at or commencing after January 1, 2019 and elected the package of transition practical expedients for expired or existing contracts, which does not require reassessment of: (1) whether any of our contracts are or contain leases, (2) lease classification and (3) initial direct costs. The Company also elected the practical expedient to adopt the new lease requirements through a cumulative effect adjustment in the period of adoption and did not adjust comparative periods. As a result of the adoption of ASC Topic 842 on January 1, 2019, the Company recorded operating right-of-use (“ROU”) assets of $8,503, operating lease liabilities of $9,016 and a cumulative effect adjustment to retained earnings for operating leases of $532. We determine if an arrangement is a lease at inception. The Company made the election to not apply the recognition requirements in ASC Topic 842 to short-term leases (i.e., leases of twelve months or less). Instead, the Company recognizes the lease payments in profit or loss on a straight-line basis over the lease term. Operating leases are included in operating lease ROU assets, current portion of operating lease liabilities, and operating lease liabilities, net of current in the Company’s condensed consolidated balance sheets. Finance leases are included in property and equipment, current portion of finance lease liabilities, and finance lease liabilities, net of current in the Company’s condensed consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. ROU assets and liabilities are recognized at the commencement date based on the present value of lease payments over the lease term. As most of the Company’s leases do not provide an implicit rate, we use our incremental borrowing rate in determining the present value of lease payments based on the information available at the commencement date. Our incremental borrowing rate reflects the estimated rate of interest that we would pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. We use the implicit rate when readily determinable. The ROU asset also includes any lease payments made and excludes lease incentives received. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term.
Goodwill	Goodwill Goodwill represents the excess of the purchase price of a business over the estimated fair value of the identifiable assets acquired and liabilities assumed. As of September 30, 2019 and December 31, 2018, the Company reported $17,236 of goodwill related to the 2014 purchase of the silo manufacturing business from Loadcraft Industries Ltd. and the 2017 purchase of the assets of Railtronix. The Company evaluates goodwill for impairment annually, as of October 31, or more often as facts and circumstances warrant. Factors such as unexpected adverse economic conditions, competition and market changes may require more frequent assessments. There was no impairment for the three and nine months ended September 30, 2019 and 2018. Before employing detailed impairment testing methodologies, the Company may first evaluate the likelihood of impairment by considering qualitative factors relevant to the business, such as macroeconomic, industry, market or any other factors that have a significant bearing on fair value. If the Company first utilizes a qualitative approach and determines that it is more likely than not that goodwill is impaired, detailed testing methodologies are then applied. Otherwise, the Company concludes that no impairment has occurred. The Company may also choose to bypass a qualitative approach and opt instead to employ detailed testing methodologies, regardless of a possible more likely than not outcome. If the Company determines through the qualitative approach that detailed testing methodologies are required, or if the qualitative approach is bypassed, the Company compares the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit.
Impairment of Long-Lived Assets and Definite-lived Intangible Assets	Impairment of Long-Lived Assets and Definite-lived Intangible Assets Long-lived assets, such as property, plant, equipment and definite-lived intangible assets, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable, such as insufficient cash flows or plans to dispose of or sell long-lived assets before the end of their previously estimated useful lives. If the carrying amount is not recoverable, the Company recognizes an impairment loss equal to the amount by which the carrying amount exceeds fair value. The Company estimates fair value based on projected future discounted cash flows. Fair value calculations for long-lived assets and intangible assets contain uncertainties because it requires the Company to apply judgment and estimates concerning future cash flows, strategic plans, useful lives and market performance. The Company also applies judgment in the selection of a discount rate that reflects the risk inherent in the current business model. There was no impairment indicators for the three and nine months ended September 30, 2019 and 2018.
Revenue Recognition	Revenue Recognition In determining the appropriate amount of revenue to be recognized as we fulfill our obligations under the agreement, the following steps must be performed at contract inception: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations, including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) we satisfy each performance obligation. Revenues from system rental consist primarily of fixed monthly fees charged to customers for the use of our patented mobile proppant management systems that unload, store and deliver proppant and chemicals at oil and natural gas well sites, which is considered to be our performance obligation. Contracts with customers are typically on thirty- to sixty-day payment terms. Revenues are recognized over time as the performance obligations are satisfied under the terms of the customer contract. We determined that the performance obligation is satisfied over time as the customer simultaneously receives and consumes the benefits provided by the entity’s performance of services, typically as our systems are used by the customer. We measure progress using an input method based on resources consumed or expended relative to the total resources expected to be consumed or expended. We typically charge our customers for the rental of our systems on a monthly basis under agreements requiring the rental of a minimum number of systems for a period of twelve months. The Company is typically entitled to short fall payments if such minimum contractual obligations are not maintained by our customers. Minimum contractual obligations have been maintained and thus the Company has not recognized revenues related to shortfalls on such take or pay contractual obligations to date. Revenues from system services consist primarily of the fees charged to customers for services including mobilization and transportation of our systems, field supervision and support and services coordinating proppant delivery to systems, each of which are considered to be separate performance obligations. Contracts with customers are typically on thirty- to sixty-day payment terms. When the Company provides system services including field supervision and support, we determined that the performance obligation is satisfied over time as the customer simultaneously receives and consumes the benefits provided by the entity’s performance of the services, typically based on fixed weekly or monthly contractual rates for field supervision and support and when the Company provides services coordinating proppant delivery. We measure progress using an input method based on resources consumed or expended relative to the total resources expected to be consumed or expended. When the Company provides mobilization and transportation of our systems on behalf of our customers, we determined that the performance obligation is satisfied at a point in time when the system has reached its intended destination. Revenues from transloading services consist primarily of the fees charged to customers for transloading proppant at our transloading facility, which is considered to be our performance obligation. Transloading services operations commenced in January 2018. We provide rail-to-truck transloading and high-efficiency sand silo storage and transloading services at the facility. Contracts with customers are typically on thirty- to sixty-day payment terms. Revenues are typically recognized over time as the customer simultaneously receives and consumes the benefits provided by the entity’s performance of the transloading service based on a throughput fee per ton rate for proppant delivered to and transloaded at the facility. We measure progress based on the proppant delivered and transloaded at the facility. Under our agreements at the facility, quarterly minimum throughput volumes are required and the Company is entitled to short fall payments if such minimum quarterly contractual obligations are not maintained. These shortfalls are based on fixed minimum volumes at a fixed rate and are recognized over time as throughput volumes transloaded are below minimum throughput volumes required. The Company recorded $221 and $522 of shortfall revenue during the three and nine months ended September 30, 2019, respectively. Revenues from inventory software services consist primarily of the fees charged to customers for the use of our Railtronix inventory management software, which is considered to be our performance obligation. Revenues are recognized over time as the customer simultaneously receives and consumes the benefits provided by the entity’s performance based on a throughput fee to monitor proppant that is loaded into a railcar, stored at a transload facility or loaded into a truck.
Deferred Revenue	Deferred Revenue Deferred revenue consists of a $25,980 partial termination payment fee received in December 2018 in accordance with a contract modification which is accounted for prospectively. The partial termination payment fee represents the distinct unsatisfied portion of a contract to provide transloading services and are considered part of the transaction price and will be allocated to the remaining performance obligations under the contract. Deferred revenues in the condensed consolidated balance sheets were $15,950 and $25,458 as of September 30, 2019 and December 31, 2018, respectively, which will be recognized as revenue from transloading services. The Company recognized $3,203 and $9,508 of deferred revenue as revenue from transloading services in the condensed consolidated statements of operations for the three and nine months ended September 30, 2019, respectively. Refer to Note 13. “Subsequent Events” for termination information on this agreement and recognition of the remaining deferred revenue. No deferred revenue was recorded or recognized as revenue during the three and nine months ended September 30, 2018.
Stock-based Compensation	Stock-based Compensation The Company accounts for its stock-based compensation including grants of restricted stock and options in the condensed consolidated statements of operations based on their fair values on the date of grant. The Company recognizes expense on a straight-line basis over the awards’ vesting period, which is generally the requisite service period.
Research and Development	Research and Development The Company expenses research and development costs as incurred, which is included in selling, general and administrative expenses in the condensed consolidated statements of operations. There were no research and development costs for the three and nine months ended September 30, 2019 and 2018.
Financial Instruments	Financial Instruments The carrying value of the Company’s financial instruments, consisting of cash, accounts receivable, notes receivable, accounts payable and insurance premium financing, approximates their fair value due to the short maturity of such instruments. Financial instruments also consist of a revolving credit facility and term loans, for which fair value approximates carrying value as the debt bears interest at a variable rate which is reflective of current rates otherwise available to the Company. As of September 30, 2019, we had no borrowings under the 2019 Credit Agreement (as defined below) outstanding. Unless otherwise noted, it is management’s opinion that the Company is not exposed to significant interest, currency or credit risks arising from these financial instruments.
Fair Value Measurements	Fair Value Measurements The Company’s financial assets and liabilities are to be measured using inputs from the three levels of the fair value hierarchy, of which the first two are considered observable and the last unobservable, which are as follows: · Level 1—Inputs are unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date; · Level 2—Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active or other inputs corroborated by observable market data for substantially the full term of the assets or liabilities; and · Level 3—Unobservable inputs that reflect the Company’s assumptions that market participants would use in pricing assets or liabilities based on the best information available.
Income Taxes	Income Taxes Solaris Inc. is a corporation and, as a result, is subject to United States federal, state and local income taxes. For the three months ended September 30, 2019 and 2018, we recognized a combined United States federal and state provision for income taxes of $3,703 and $4,237, respectively. For the nine months ended September 30, 2019 and 2018, we recognized a combined United States federal and state provision for income taxes of $12,042 and $9,541, respectively. Solaris LLC is treated as a partnership for United States federal income tax purposes and therefore does not pay United States federal income tax on its taxable income. Instead, the Solaris LLC members are liable for United States federal income tax on their respective shares of the Company’s taxable income reported on the members’ United States federal income tax returns. Our revenues are derived through transactions in several states, which may be subject to state and local taxes. Accordingly, we have recorded a liability for state and local taxes that management believes is adequate for activities as of September 30, 2019 and December 31, 2018. We account for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events included in the condensed consolidated financial statements. Under this method, we determine deferred tax assets and liabilities on the basis of the differences between the book value and tax bases of assets and liabilities by using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period in which the enactment date occurs. We recognize deferred tax assets to the extent we believe these assets are more-likely-than-not to be realized. In making such a determination, we consider all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax planning strategies and recent results of operations. We record uncertain tax positions on the basis of a two-step process in which (1) we determine whether it is more-likely-than-not the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions meeting the more-likely-than-not recognition threshold, we recognize the largest amount of tax benefit that is more than 50% likely to be realized upon ultimate settlement with the related tax authority. Interest and penalties related to income taxes are included in the benefit (provision) for income taxes in our condensed consolidated statement of operations. We have not incurred any significant interest or penalties related to income taxes in any of the periods presented. See Note 9. “Income Taxes” for additional information regarding income taxes.
Payable Related to the Tax Receivable Agreement	Payable Related to the Tax Receivable Agreement In connection with the Solaris Inc.’s initial public offering (the “IPO” or the “Offering”), Solaris Inc. entered into a Tax Receivable Agreement (the “Tax Receivable Agreement”) with the members of Solaris LLC immediately prior to the IPO (each such person and any permitted transferee, a “TRA Holder,” and together, the “TRA Holders”) on May 17, 2017. This agreement generally provides for the payment by Solaris Inc. to each TRA Holder of 85% of the net cash savings, if any, in United States federal, state and local income tax and franchise tax that Solaris Inc. actually realizes (computed using simplifying assumptions to address the impact of state and local taxes) or is deemed to realize in certain circumstances in periods after the IPO as a result of (i) certain increases in tax basis that occur as a result of Solaris Inc.’s acquisition (or deemed acquisition for United States federal income tax purposes) of all or a portion of such TRA Holder’s Solaris LLC Units in connection with the IPO or pursuant to the exercise of the Redemption Right or the Call Right (each as defined in Solaris LLC’s Second Amended and Restated Limited Liability Company Agreement (the “Solaris LLC Agreement”)) and (ii) imputed interest deemed to be paid by Solaris Inc. as a result of, and additional tax basis arising from, any payments Solaris makes under the Tax Receivable Agreement. Solaris Inc. will retain the benefit of the remaining 15% of these cash savings. As of September 30, 2019 and December 31, 2018, Solaris Inc. recorded a payable related to the Tax Receivable Agreement of $67,987 and $56,149, respectively. The increase in payables related to the Tax Receivable Agreement is a result of Solaris Inc.’s acquisition (or deemed acquisition for United States federal income tax purposes) of Solaris LLC Units from TRA Holders during the nine months ended September 30, 2019.
Environmental Matters	Environmental Matters The Company is subject to various federal, state and local laws and regulations relating to the protection of the environment. Management has established procedures for the ongoing evaluation of the Company’s operations, to identify potential environmental exposures and to comply with regulatory policies and procedures. Environmental expenditures that relate to current operations are expensed or capitalized as appropriate. Expenditures that relate to an existing condition caused by past operations and do not contribute to current or future revenue generation are expensed as incurred. Liabilities are recorded when environmental costs are probable, and the costs can be reasonably estimated. The Company maintains insurance which may cover in whole or in part certain environmental expenditures. As of September 30, 2019 and December 31, 2018, there were no environmental matters deemed probable.
Segment Information	Segment Information Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, or decision-making group, in making decisions on how to allocate resources and assess performance. The Company’s chief operating decision maker is the Chief Executive Officer. The Company and the Chief Executive Officer view the Company’s operations and manage its business as one operating segment. All long-lived assets of the Company reside in the United States.
Recent Accounting Standards	Accounting Standards Recently Issued But Not Yet Adopted There are no accounting standards recently issued, but not yet adopted which are expected to impact our condensed consolidated financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2019
Summary of Significant Accounting Policies
Schedule of useful life of property, plant and equipment	Useful Life Systems and related equipment Up to 15 years Machinery and equipment 3-10 years Furniture and fixtures 5 years Computer hardware and software 3-10 years Vehicles 5 years Transloading facility and equipment 15-30 years Buildings and leasehold improvements 15 years
Schedule of intangible assets by major classification	Accumulated Net Book Gross Amortization Value As of September 30, 2019: Customer relationships $ 4,703 $ (1,232) $ 3,471 Software acquired in the acquisition of Railtronix 346 (91) 255 Non-competition agreement 225 (82) 143 Patents and other 114 (27) 87 Total identifiable intangibles $ 5,388 $ (1,432) $ 3,956 As of December 31, 2018: Customer relationships $ 4,703 $ (727) $ 3,976 Software acquired in the acquisition of Railtronix 346 (54) 292 Non-competition agreement 225 (49) 176 Patents and other 114 (18) 96 Total identifiable intangibles $ 5,388 $ (848) $ 4,540

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	9 Months Ended
	Sep. 30, 2019
Prepaid Expenses and Other Current Assets.
Schedule of prepaid expenses and other current assets	September 30, December 31, 2019 2018 Prepaid purchase orders $ 1,106 $ 2,802 Prepaid insurance 1,481 576 Deposits 901 882 Incentive receivables and other assets 1,758 1,232 Prepaid expenses and other current assets $ 5,246 $ 5,492

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	9 Months Ended
	Sep. 30, 2019
Property, Plant and Equipment.
Schedule of property plant and equipment	September 30, December 31, 2019 2018 Systems and related equipment $ 287,565 $ 258,600 Systems in process 16,437 11,245 Transloading facility and equipment 40,254 40,218 Computer hardware and software 1,238 1,185 Machinery and equipment 5,216 5,126 Vehicles 8,044 8,334 Buildings 4,339 4,280 Land 612 612 Furniture and fixtures 284 282 Property, plant and equipment, gross 363,989 329,882 Less: accumulated depreciation (52,736) (33,344) Property, plant and equipment, net $ 311,253 $ 296,538

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	9 Months Ended
	Sep. 30, 2019
Accrued Liabilities
Schedule of accrued liabilities	September 30, December 31, 2019 2018 Property, plant and equipment $ 194 $ 2,153 Employee related expenses 3,996 4,500 Selling, general and administrative 1,491 944 Cost of revenue 5,700 2,702 Excise, franchise and sales taxes 4,045 1,461 Ad valorem taxes 1,306 774 Other 102 124 Accrued liabilities $ 16,834 $ 12,658

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2019
Leases
Schedule of components of lease expense	Three Months Ended Nine Months Ended September 30, 2019 September 30, 2019 Operating lease cost (1) (2) $ 297 $ 890 Finance lease cost Amortization of ROU assets 8 25 Interest on lease liabilities 1 1 Total finance lease cost $ 9 $ 26 (1) Includes short term leases. (2) Operating lease costs of $185, $20 and $92 were reported in Selling, general and administrative, Cost of system services and Cost of transloading services for the three months ended September 30, 2019, respectively. Operating lease costs of $556, $58 and $276 were reported in Selling, general and administrative, Cost of system services and Cost of transloading services for the nine months ended September 30, 2019, respectively. No variable lease costs were recognized during the three and nine months ended September 30, 2019.
Schedule of non-cancellable operating leases as of December 31, 2018	Year Ending December 31, Amount 2019 $ 1,432 2020 1,375 2021 1,299 2022 1,093 2023 1,092 Thereafter 9,725 Total minimum lease payments $ 16,016
Schedule of future minimum operating lease payments	Future minimum lease payments under non-cancellable leases as of September 30, 2019 were as follows: Year Ending December 31, Operating Leases Finance Leases 2019 (remainder of) $ 243 14 2020 1,116 35 2021 1,060 33 2022 1,091 33 2023 1,100 33 Thereafter 9,463 36 Total future minimum lease payments 14,073 184 Less: effects of discounting (5,514) (17) Total lease liabilities $ 8,559 $ 167
Schedule of future minimum finance lease payments	Year Ending December 31, Operating Leases Finance Leases 2019 (remainder of) $ 243 14 2020 1,116 35 2021 1,060 33 2022 1,091 33 2023 1,100 33 Thereafter 9,463 36 Total future minimum lease payments 14,073 184 Less: effects of discounting (5,514) (17) Total lease liabilities $ 8,559 $ 167
Schedule of other information	Supplemental cash flow information related to leases was as follows: Three Months Ended Nine Months Ended September 30, 2019 September 30, 2019 Supplemental Cash Flows Information Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 243 $ 877 Financing cash flows from finance leases 9 26 Other information related to leases was as follows: September 30, 2019 Weighted Average Remaining Lease Term Operating leases 13.9 years Finance leases 5.4 years Weighted Average Discount Rate Operating leases Finance leases

Equity (Tables)

Equity (Tables)	9 Months Ended
	Sep. 30, 2019
Equity
Summary of activity related to restricted stock	Restricted Stock Awards 2019 2018 Unvested at January 1, 411,497 1,218,265 Awarded 375,068 2,120 Vested (706) — Forfeited (405) (848) Unvested at March 31, 785,454 1,219,537 Awarded 29,847 — Vested (67,674) (345,520) Forfeited (7,896) (21,495) Unvested at June 30, 739,731 852,522 Awarded 43,830 86,544 Vested (138,821) (297,371) Forfeited (9,644) (223,988) Unvested at September 30, 635,096 417,707
Schedule of earnings per share calculation	Three Months Ended September 30, Nine Months Ended September 30, Basic net income per share: 2019 2018 2019 2018 Numerator Net income attributable to Solaris $ 11,398 $ 13,019 $ 36,991 $ 29,546 Less income attributable to participating securities (1) (245) (251) (817) (1,042) Net income attributable to common stockholders $ 11,153 $ 12,768 $ 36,174 $ 28,504 Denominator Weighted average number of unrestricted outstanding common shares used to calculate basic net income per share 30,951 26,197 27,270 25,216 Effect of dilutive securities: Stock options 29 132 47 164 Diluted weighted-average shares of Class A common stock outstanding used to calculate diluted net income per share 30,980 26,329 27,317 25,380 Earnings per share of Class A common stock - basic $ 0.36 0.49 1.33 1.13 Earnings per share of Class A common stock - diluted $ 0.36 0.49 1.33 1.12 (1) The Company’s restricted shares of common stock are participating securities.
Schedule of antidilutive shares	Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Class B common stock 15,939 20,398 15,598 21,085 Restricted stock awards 129 195 242 524 Total 16,068 20,593 15,840 21,609

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies
Schedule of contractual obligation future payments	The table below provides estimates of the timing of future payments that we are contractually obligated to make based on agreements in place at September 30, 2019: For the Year Ending December 31, 2019 2020 2021 2022 2023 Thereafter Total (in thousands) Operating lease obligations (1) $ 243 $ 1,116 $ 1,060 $ 1,091 $ 1,100 $ 9,463 $ 14,073 Finance lease obligations (2) 14 35 33 33 33 36 184 Commitment fees on Revolving Loan (3) 32 125 125 40 — — 322 Purchase commitments (4) — 2,588 2,217 — — — 4,805 Other commitments 32 274 255 37 2 — 600 Total $ 321 $ 4,138 $ 3,690 $ 1,201 $ 1,135 $ 9,499 19,984 (1) (2) (3) (4)

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Summary of Significant Accounting Policies
Accounts receivable due maximum period	60 days
Allowance for doubtful accounts	$ 0	$ 0
Inventory impairment	$ 0		$ 0

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Property (Details)	9 Months Ended
	Sep. 30, 2019
Systems and related equipment | Maximum
Property, Plant and Equipment
Property, plant and equipment useful life	15 years
Machinery and equipment | Minimum
Property, Plant and Equipment
Property, plant and equipment useful life	3 years
Machinery and equipment | Maximum
Property, Plant and Equipment
Property, plant and equipment useful life	10 years
Furniture and fixtures
Property, Plant and Equipment
Property, plant and equipment useful life	5 years
Computer hardware and software | Minimum
Property, Plant and Equipment
Property, plant and equipment useful life	3 years
Computer hardware and software | Maximum
Property, Plant and Equipment
Property, plant and equipment useful life	10 years
Vehicles
Property, Plant and Equipment
Property, plant and equipment useful life	5 years
Transloading facility and equipment | Minimum
Property, Plant and Equipment
Property, plant and equipment useful life	15 years
Transloading facility and equipment | Maximum
Property, Plant and Equipment
Property, plant and equipment useful life	30 years
Buildings and leasehold improvements
Property, Plant and Equipment
Property, plant and equipment useful life	15 years

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Intangible assets by major classification
Intangible amortization expense	$ 195	$ 195	$ 584	$ 606
Gross	5,388		5,388		$ 5,388
Accumulated Amortization	(1,432)		(1,432)		(848)
Net Book Value	3,956		3,956		4,540
Goodwill	17,236		17,236		17,236
Goodwill impairment	0	0	0	0
Impairment of long-lived assets	0	0	0	0
Impairment of definite-lived intangible assets	0	$ 0	0	$ 0
Customer relationships
Intangible assets by major classification
Gross	4,703		4,703		4,703
Accumulated Amortization	(1,232)		(1,232)		(727)
Net Book Value	3,471		3,471		3,976
Computer software
Intangible assets by major classification
Gross	346		346		346
Accumulated Amortization	(91)		(91)		(54)
Net Book Value	255		255		292
Non-competition agreement
Intangible assets by major classification
Gross	225		225		225
Accumulated Amortization	(82)		(82)		(49)
Net Book Value	143		143		176
Patents and other
Intangible assets by major classification
Gross	114		114		114
Accumulated Amortization	(27)		(27)		(18)
Net Book Value	$ 87		$ 87		$ 96
Minimum
Intangible assets by major classification
Definite-lived intangible assets useful life			5 years
Maximum
Intangible assets by major classification
Definite-lived intangible assets useful life			15 years

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Leases (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Summary of Significant Accounting Policies
Lease, Practical Expedients, Package [true false]	true
ROU assets	$ 8,032
Operating lease liabilities	8,559
Retained earnings	$ 62,517		$ 35,507
ASU 2016-02 | Adjustment
Summary of Significant Accounting Policies
ROU assets		$ 8,503
Operating lease liabilities		9,016
Retained earnings		$ (532)

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Revenue (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Dec. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Summary of Significant Accounting Policies
Shortfall revenue		$ 221		$ 522
Termination payment received	$ 25,980
Remaining deferred revenue	$ 25,458	15,950		15,950
Deferred revenue recognized		$ 3,203	$ 0	$ 9,508	$ 0
System rental | Minimum
Summary of Significant Accounting Policies
Payment terms				30 days
System rental | Maximum
Summary of Significant Accounting Policies
Payment terms				60 days
System services | Minimum
Summary of Significant Accounting Policies
Payment terms				30 days
System services | Maximum
Summary of Significant Accounting Policies
Payment terms				60 days
Transloading services | Minimum
Summary of Significant Accounting Policies
Payment terms				30 days
Transloading services | Maximum
Summary of Significant Accounting Policies
Payment terms				60 days

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Misc (Details) $ in Thousands	May 17, 2017	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2019USD ($)segment	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Provision for income taxes		$ 3,703	$ 4,237	$ 12,042	$ 9,541
Payables related to Tax Receivable Agreement		67,987		67,987		$ 56,149
Environmental matters deemed probable				$ 0		0
Number of operating segments | segment				1
Tax Receivable Agreement
Payments of net cash saving (as a percent)	85.00%			85.00%
Payables related to Tax Receivable Agreement		67,987		$ 67,987		$ 56,149
Benefit of remaining cash savings (as a percent)	15.00%
2019 Credit Agreement
Outstanding credit facility		$ 0		$ 0

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Prepaid Expenses and Other Current Assets.
Prepaid purchase orders	$ 1,106	$ 2,802
Prepaid insurance	1,481	576
Deposits	901	882
Incentive receivables and other assets	1,758	1,232
Prepaid expenses and other current assets	$ 5,246	$ 5,492

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment
Property, plant and equipment, gross	$ 363,989	$ 329,882
Less: accumulated depreciation	(52,736)	(33,344)
Property, plant and equipment, net	311,253	296,538
Systems and related equipment
Property, Plant and Equipment
Property, plant and equipment, gross	287,565	258,600
Systems in process
Property, Plant and Equipment
Property, plant and equipment, gross	16,437	11,245
Transloading facility and equipment
Property, Plant and Equipment
Property, plant and equipment, gross	40,254	40,218
Computer hardware and software
Property, Plant and Equipment
Property, plant and equipment, gross	1,238	1,185
Machinery and equipment
Property, Plant and Equipment
Property, plant and equipment, gross	5,216	5,126
Vehicles
Property, Plant and Equipment
Property, plant and equipment, gross	8,044	8,334
Buildings
Property, Plant and Equipment
Property, plant and equipment, gross	4,339	4,280
Land
Property, Plant and Equipment
Property, plant and equipment, gross	612	612
Furniture and fixtures
Property, Plant and Equipment
Property, plant and equipment, gross	$ 284	$ 282

Property, Plant and Equipment -

Property, Plant and Equipment - Depreciation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Property, Plant and Equipment
Depreciation expense	$ 6,713	$ 5,133	$ 19,291	$ 11,908
Capitalized depreciation in property, plant and equipment	187	182	559	501
Selling, general and administrative expenses
Property, Plant and Equipment
Depreciation expense	145	124	406	347
System rental
Property, Plant and Equipment
Depreciation expense	5,773	4,133	16,481	10,128
System services
Property, Plant and Equipment
Depreciation expense	384	347	1,173	889
Transloading services
Property, Plant and Equipment
Depreciation expense	$ 411	$ 529	$ 1,231	$ 544

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Accrued Liabilities
Property, plant and equipment	$ 194	$ 2,153
Employee related expenses	3,996	4,500
Selling, general and administrative	1,491	944
Cost of revenue	5,700	2,702
Excise, franchise and sales taxes	4,045	1,461
Ad valorem taxes	1,306	774
Other	102	124
Accrued liabilities	$ 16,834	$ 12,658

Leases (Details)

Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Leases
Property, plant and equipment, cost	$ 363,989	$ 329,882
Accumulated depreciation	52,736	33,344
Finance leased assets
Leases
Property, plant and equipment, cost	299	299
Accumulated depreciation	$ 101	$ 85
Kingfisher Facility
Leases
Term	30 years

Leases - Lease cost (Details)

Leases - Lease cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Components of lease expenses:
Operating lease cost	$ 297	$ 890
Amortization of ROU assets	8	25
Interest on lease liabilities	1	1
Total finance lease cost	9	26
Variable lease costs	0	0
Selling, general and administrative expenses
Components of lease expenses:
Operating lease cost	185	556
Cost of sales | System rental
Components of lease expenses:
Operating lease cost	20	58
Cost of sales | Transloading services
Components of lease expenses:
Operating lease cost	$ 92	$ 276

Leases - Maturities (Details)

Leases - Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Non-cancellable operating leases as of December 31, 2018
2019		$ 1,432
2020		1,375
2021		1,299
2022		1,093
2023		1,092
Thereafter		9,725
Total minimum lease payments		$ 16,016
Operating lease obligations
2019 (remainder of)	$ 243
2020	1,116
2021	1,060
2022	1,091
2023	1,100
Thereafter	9,463
Total future minimum lease payments	14,073
Less: effects of discounting	(5,514)
Total lease liabilities	8,559
Finance lease obligations
2019 (remainder of)	14
2020	35
2021	33
2022	33
2023	33
Thereafter	36
Total future minimum lease payments	184
Less: effects of discounting	(17)
Total lease liabilities	$ 167

Leases - Other (Details)

Leases - Other (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018
Leases
Operating cash flows from operating leases	$ 243	$ 877
Financing cash flows from finance leases	$ 9	$ 26	$ 21
Weighted Average Remaining Lease Term - Operating leases	13 years 10 months 24 days	13 years 10 months 24 days
Weighted Average Remaining Lease Term - Finance leases	5 years 4 months 24 days	5 years 4 months 24 days
Weighted Average Discount Rate - Operating leases	6.30%	6.30%
Weighted Average Discount Rate - Finance leases	3.30%	3.30%

Senior Secured Credit Facility

Senior Secured Credit Facility (Details) $ in Thousands	Apr. 26, 2019USD ($)	Jan. 19, 2018USD ($)	Sep. 30, 2019USD ($)	Dec. 31, 2018USD ($)
2019 Credit Agreement
Senior Secured Credit Facility
Maximum borrowing	$ 50,000
Potential additional borrowing available	25,000
Maximum borrowing capacity with accordion option	$ 75,000
Commitment fee (as a percent)			0.25%
Indebtedness to consolidated EBITDA	2.75
Senior indebtedness to consolidated EBITDA	2.50
Eligible accounts (as a percent)	100.00%
Eligible accounts to revolving exposure ratio	1
Leverage ratio for threshold	2
Cash adjustment to net indebtedness	$ 3,000
Leverage ratio for debt repayment	1
Cash threshold triggering repayment	$ 20,000
Cash threshold over a period of time triggering repayment	$ 5,000
Period for cash threshold repayment trigger	180 days
Maximum capital expenditures allowed	$ 100,000
Outstanding credit facility			$ 0
Remaining borrowing capacity			$ 50
2019 Credit Agreement | Minimum
Senior Secured Credit Facility
Commitment fee (as a percent)	0.25%
2019 Credit Agreement | Maximum
Senior Secured Credit Facility
Commitment fee (as a percent)	0.375%
2019 Credit Agreement | Eurodollar | Minimum
Senior Secured Credit Facility
Applicable margin rate	1.75%
2019 Credit Agreement | Eurodollar | Maximum
Senior Secured Credit Facility
Applicable margin rate	2.50%
2019 Credit Agreement | Alternate base rate | Minimum
Senior Secured Credit Facility
Applicable margin rate	0.75%
2019 Credit Agreement | Alternate base rate | Maximum
Senior Secured Credit Facility
Applicable margin rate	1.50%
2018 Credit Agreement
Senior Secured Credit Facility
Outstanding credit facility				$ 13,000
2018 Credit Agreement | LIBOR | Minimum
Senior Secured Credit Facility
Applicable margin rate		3.00%
2018 Credit Agreement | LIBOR | Maximum
Senior Secured Credit Facility
Applicable margin rate		3.50%
Advance Loan
Senior Secured Credit Facility
Maximum borrowing		$ 50,000
Revolving Loan
Senior Secured Credit Facility
Maximum borrowing		20,000
Potential additional borrowing available		$ 10,000
Weighted average interest rate (as a percent)			5.49%
Revolving Loan | Minimum
Senior Secured Credit Facility
Commitment fee (as a percent)		0.25%
Revolving Loan | Maximum
Senior Secured Credit Facility
Commitment fee (as a percent)		0.50%

Equity - Dividends (Details)

Equity - Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 26, 2019	Jun. 26, 2019	Mar. 29, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2019
Stock-based compensation
Cash dividends paid (in dollars per share)	$ 0.10	$ 0.10	$ 0.10	$ 0.1	$ 0.1	$ 0.1
Distributions paid to unit holders							$ 14,274
Distributions paid to unit holders (in dollars per unit)				$ 0.10		$ 0.10
Distribution received	$ 3,165	$ 3,164	$ 3,119
Dividend paid to common stock	3,165	3,164	3,119
Dividends paid to restricted stock	64	74	79
Solaris LLC
Stock-based compensation
Distributions paid to unit holders	$ 4,759	$ 4,758	$ 4,757
Distributions paid to unit holders (in dollars per unit)	$ 0.10	$ 0.10	$ 0.10

Equity - SBC (Details)

Equity - SBC (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Stock-based compensation
Stock-based compensation expense	$ 1,225	$ 338	$ 3,265	$ 3,140
Options
Stock-based compensation
Options granted (in shares)			591,261
Options granted (in dollars per shares)			$ 2.87
Options grant date fair value (in dollars per shares)			$ 12.04
Options exercised (in shares)			522,285
Forfeited (in shares)			33,348
Options outstanding (in shares)	35,628		35,628
Vesting period			4 years
Stock-based compensation expense	$ 0	$ 0	$ 0	$ 0
Class A Common Stock
Stock-based compensation
Reserved for issuance (in shares)	5,118,080		5,118,080

Equity - Restricted stock (Deta

Equity - Restricted stock (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Other non-option information
Stock-based compensation expense	$ 1,225			$ 338			$ 3,265	$ 3,140
Selling, general and administrative expenses
Other non-option information
Stock-based compensation expense	1,139			286			3,042	3,002
System rental
Other non-option information
Stock-based compensation expense	10						24	5
System services
Other non-option information
Stock-based compensation expense	71			51			187	132
Transloading services
Other non-option information
Stock-based compensation expense	$ 5			$ 1			$ 12	$ 1
Restricted stock
Number of Shares
Unvested, beginning (in shares)	739,731	785,454	411,497	852,522	1,219,537	1,218,265	411,497	1,218,265
Awarded (in shares)	43,830	29,847	375,068	86,544		2,120
Vested (in shares)	(138,821)	(67,674)	(706)	(297,371)	(345,520)
Forfeited (in shares)	(9,644)	(7,896)	(405)	(223,988)	(21,495)	(848)
Unvested, end (in shares)	635,096	739,731	785,454	417,707	852,522	1,219,537	635,096	417,707
Restricted stock | First vesting period
Number of Shares
Unvested, end (in shares)	1,497						1,497
Restricted stock | Second vesting period
Number of Shares
Unvested, end (in shares)	350,907						350,907
Restricted stock | Third vesting period
Number of Shares
Unvested, end (in shares)	149,688						149,688
Restricted stock | Fourth vesting period
Number of Shares
Unvested, end (in shares)	133,004						133,004
Restricted stock | Selling, general and administrative expenses
Other non-option information
Stock-based compensation expense	$ 1,139						$ 3,042
Restricted stock | Property, Plant and Equipment
Other non-option information
Stock-based compensation expense	37						133
Restricted stock | System rental
Other non-option information
Stock-based compensation expense	10						24
Restricted stock | System services
Other non-option information
Stock-based compensation expense	71						187
Restricted stock | Transloading services
Other non-option information
Stock-based compensation expense	$ 5						$ 12

Equity - EPS (Details)

Equity - EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Numerator
Net income attributable to Solaris	$ 11,398	$ 13,019	$ 36,991	$ 29,546
Less income attributable to participating securities	(245)	(251)	(817)	(1,042)
Net income attributable to common stockholders	$ 11,153	$ 12,768	$ 36,174	$ 28,504
Class A Common Stock
Denominator
Weighted average number of unrestricted outstanding common shares used to calculate basic net income per share (in shares)	30,951	26,197	27,270	25,216
Effect of dilutive securities:
Stock options (in shares)	29	132	47	164
Diluted weighted-average shares of Class A common stock outstanding used to calculate diluted net income per share (in shares)	30,980	26,329	27,317	25,380
Earnings per share of Class A common stock - basic (in dollars per share)	$ 0.36	$ 0.49	$ 1.33	$ 1.13
Earnings per share of Class A common stock - diluted (in dollars per share)	$ 0.36	$ 0.49	$ 1.33	$ 1.12

Equity - Antidilutive (Details)

Equity - Antidilutive (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Potentially dilutive shares
Excluded from EPS calculation (in shares)	16,068	20,593	15,840	21,609
Class B Common Stock
Potentially dilutive shares
Excluded from EPS calculation (in shares)	15,939	20,398	15,598	21,085
Restricted stock
Potentially dilutive shares
Excluded from EPS calculation (in shares)	129	195	242	524

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	May 17, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Effective tax rate		14.80%	13.98%	14.88%	13.54%
Unrecognized tax benefits				$ 816
Payables related to Tax Receivable Agreement		$ 67,987		67,987		$ 56,149
Tax Receivable Agreement
Payables related to Tax Receivable Agreement		$ 67,987		$ 67,987		$ 56,149
Percentage of Net Cash Saving	85.00%			85.00%

Concentrations (Details)

Concentrations (Details) - item	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Customer | Revenue
Concentrations
Number of customers	2	2	4	3
Customer | Revenue | Customer One
Concentrations
Concentration risk (as a percent)	14.00%	13.00%	14.00%	16.00%
Customer | Revenue | Customer Two
Concentrations
Concentration risk (as a percent)	12.00%	10.00%	11.00%	10.00%
Customer | Revenue | Customer Three
Concentrations
Concentration risk (as a percent)			11.00%	10.00%
Customer | Revenue | Customer Four
Concentrations
Concentration risk (as a percent)			10.00%
Customer | Accounts receivable
Concentrations
Number of customers			4		3
Customer | Accounts receivable | Customer One
Concentrations
Concentration risk (as a percent)			14.00%		20.00%
Customer | Accounts receivable | Customer Two
Concentrations
Concentration risk (as a percent)			14.00%		10.00%
Customer | Accounts receivable | Customer Three
Concentrations
Concentration risk (as a percent)			12.00%		10.00%
Customer | Accounts receivable | Customer Four
Concentrations
Concentration risk (as a percent)			10.00%
Supplier | Purchases
Concentrations
Number of suppliers	1	2	1	2
Concentration risk (as a percent)	38.00%		17.00%
Supplier | Purchases | Supplier One
Concentrations
Concentration risk (as a percent)		17.00%		14.00%
Supplier | Purchases | Supplier Two
Concentrations
Concentration risk (as a percent)		12.00%		12.00%
Supplier | Accounts payables
Concentrations
Number of suppliers			1		1
Concentration risk (as a percent)			77.00%		13.00%

Commitments and Contingencies_2

Commitments and Contingencies (Details) $ in Thousands	1 Months Ended	9 Months Ended
	Jun. 30, 2018USD ($)	Sep. 30, 2019USD ($)item	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Operating lease obligations
2019 (remainder of)		$ 243
2020		1,116
2021		1,060
2022		1,091
2023		1,100
Thereafter		9,463
Total future minimum lease payments		14,073
Finance lease obligations
2019 (remainder of)		14
2020		35
2021		33
2022		33
2023		33
Thereafter		36
Total future minimum lease payments		184
Commitment fees on Revolving Loan
2019		32
2020		125
2021		125
2022		40
Total		322
Purchase commitments
2020		2,588
2021		2,217
Total		4,805
Other commitments
2019		32
2020		274
2021		255
2022		37
2023		2
Total		600
Total
2019		321
2020		4,138
2021		3,690
2022		1,201
2023		1,135
Thereafter		9,499
Total		$ 19,984
Railtronix LLC
Other Commitments
Performance-based cash awards liability				$ 2,500
Number of completed milestones | item		1
Contingent consideration payment	$ 1,625
Raw material purchases
Other commitments
Total		$ 4,805	$ 18,998
Solaris Energy Management, LLC
Other commitments
Total		$ 9,477
2019 Credit Agreement
Commitment fees on Revolving Loan
Commitment fee (as a percent)		0.25%
Kingfisher Facility
Operating lease obligations
Term		30 years

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Related Party Transactions
Due from related party	$ 231		$ 231		$ 232
Due to related party	78		78		$ 103
William A. Zartler
Related Party Transactions
Payment made to related party	$ 217	$ 164	$ 836	$ 503

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ in Thousands	1 Months Ended
	Oct. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Subsequent Events
Termination payment received		$ 25,980
Remaining deferred revenue		$ 25,458	$ 15,950
Subsequent Event
Subsequent Events
Termination payment received	$ 1,680
Remaining deferred revenue	$ 17,630