Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation and Consolidation The accompanying Condensed Consolidated Financial Statements (the “Financial Statements”) of U.S. Silica Holdings, Inc. (“Holdings,” and together with its subsidiaries “we,” “us” or the “Company”) included in this Quarterly Report on Form 10-Q, have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X issued by the U.S. Securities and Exchange Commission (“SEC”). They do not contain certain information included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2016; therefore, the interim Condensed Consolidated Financial Statements should be read in conjunction with that Annual Report on Form 10-K. In the opinion of management, all adjustments necessary for a fair presentation of the Financial Statements have been included. Such adjustments are of a normal, recurring nature. In order to make this report easier to read, we refer throughout to (i) our Condensed Consolidated Balance Sheets as our “Balance Sheets,” (ii) our Condensed Consolidated Statements of Operations as our “Income Statements,” and (iii) our Condensed Consolidated Statements of Cash Flows as our “Cash Flows.” On April 1, 2017, we completed the acquisition of White Armor, a product line of cool roof granules used in industrial roofing applications. On May 17, 2017, we purchased reserves in Crane County, Texas. Unaudited Interim Financial Statements The accompanying Balance Sheet as of June 30, 2017; the Income Statements and Condensed Consolidated Statements of Comprehensive Income for the three and six months ended June 30, 2017 and 2016, respectively; the Condensed Consolidated Statements of Stockholders' Equity and Cash Flows for the six months ended June 30, 2017; and other information disclosed in the related notes are unaudited. The Balance Sheet as of December 31, 2016, was derived from our audited consolidated financial statements as included in our 2016 Annual Report. Use of Estimates and Assumptions The preparation of the Financial Statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the related disclosure of contingent assets and liabilities at the date of the Financial Statements and the reported amounts of revenues and expenses during the reporting period. The more significant areas requiring the use of management estimates and assumptions relate to purchase price allocation for businesses acquired; mineral reserves that are the basis for future cash flow estimates utilized in impairment calculations and units-of-production amortization calculations; environmental, reclamation and closure obligations; estimates of recoverable minerals; estimates of allowance for doubtful accounts; estimates of fair value for certain reporting units and asset impairments (including impairments of goodwill and other long-lived assets); write-downs of inventory to net realizable value; equity-based compensation expense; post-employment, post-retirement and other employee benefit liabilities; valuation allowances for deferred tax assets; contingent considerations; reserves for contingencies and litigation and the fair value and accounting treatment of financial instruments including derivative instruments. We base our estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances. Accordingly, actual results may differ significantly from these estimates under different assumptions or conditions. Recently Issued Accounting Pronouncements In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update (“ASU”)2014-09, Revenue from Contracts with Customers, which supersedes previous revenue recognition guidance. The new guidance introduces a new principles-based framework for revenue recognition and disclosure. Since its issuance, the FASB has issued an additional six ASUs, including ASU 2016-20 in December 2016, amending the guidance and the effective dates of amendments, and the SEC has rescinded certain related SEC guidance; the most recent of which was issued in May 2016. The pronouncements are effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within that reporting period. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. We have not yet completed our final review of the impact of this guidance, although we currently do not anticipate a material impact on our revenue recognition practices. In 2017, the Company identified a project team and commenced an initial impact assessment process for ASU 2014-09. To date, the Company has reviewed a sample of contracts with its customers and made preliminary assessments of the impact on revenue and expenses based on these reviews; however, the assessment of the impact to the Company’s results of operations, financial position and cash flows as a result of this guidance is ongoing. The Company will adopt this new standard as of January 1, 2018, and currently expects to apply the modified retrospective method, which may result in a cumulative effect adjustment as of the date of adoption. Both the Company’s initial assessment and its selected transition method may change depending on the results of the Company’s final assessment of the impact to its financial statements. In January 2017, the FASB issued ASU 2017-04 Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment, which removes Step 2 from the goodwill impairment test. It is effective for annual and interim periods beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed with a measurement date after January 1, 2017. We are currently evaluating the impact of this accounting standard on our consolidated financial statements. In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business ("ASU 2017-01"). The new guidance clarifies the definition of a business with the objective of adding guidance to assist companies and other reporting organizations with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The changes to the definition of a business will likely result in more acquisitions being accounted for as asset acquisitions. ASU 2017-01 is effective for annual periods beginning after December 15, 2017, including interim periods within those periods. Early application of the amendments in ASU 2017-01 is allowed for transactions for which the acquisition date occurs before the issuance date or effective date of the amendments, only when the transaction has not been reported in financial statements that have been issued or made available for issuance. In March 2017, the FASB issued ASU 2017-07 Compensation-Retirement Benefits (Topic 715), Improving the Presentation of Net Periodic Pension Cost and Net Periodic Post-retirement Benefit ("ASU 2017-07"). ASU 2017-07 amends presentation requirements related to reporting the service cost component of net benefit costs to require that the service cost component be reported in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period, disaggregating the component from other net benefit costs. ASU 2017-07 also limits the components of net benefit cost eligible to be capitalized to service cost. ASU 2017-07 is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods for public business entities. We are currently evaluating the impact of this accounting standard on our consolidated financial statements. In May 2017, the FASB issued ASU 2017-09 Compensation-Stock Compensation (Topic 718), Scope of Modification Accounting ("ASU 2017-09"). This Update amends the scope of modification for share-based payment arrangements. This ASU 2017-09 provides guidance on the types of the changes to the terms or conditions of share-based payments awards to which an entity would be required to apply modification accounting. Specifically, an entity would not apply modification accounting if the fair value, vesting conditions, and classification of the awards are the same immediately before and after the modification. ASU 2017-09 is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods for all entities. We are currently evaluating the impact of this accounting standard on our consolidated financial statements.

NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation and Consolidation

The accompanying Condensed Consolidated Financial Statements (the “Financial Statements”) of U.S. Silica Holdings, Inc. (“Holdings,” and together with its subsidiaries “we,” “us” or the “Company”) included in this Quarterly Report on Form 10-Q, have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X issued by the U.S. Securities and Exchange Commission (“SEC”). They do not contain certain information included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2016; therefore, the interim Condensed Consolidated Financial Statements should be read in conjunction with that Annual Report on Form 10-K. In the opinion of management, all adjustments necessary for a fair presentation of the Financial Statements have been included. Such adjustments are of a normal, recurring nature.

In order to make this report easier to read, we refer throughout to (i) our Condensed Consolidated Balance Sheets as our “Balance Sheets,” (ii) our Condensed Consolidated Statements of Operations as our “Income Statements,” and (iii) our Condensed Consolidated Statements of Cash Flows as our “Cash Flows.”

On April 1, 2017, we completed the acquisition of White Armor, a product line of cool roof granules used in industrial roofing applications. On May 17, 2017, we purchased reserves in Crane County, Texas.

Unaudited Interim Financial Statements

The accompanying Balance Sheet as of June 30, 2017; the Income Statements and Condensed Consolidated Statements of Comprehensive Income for the three and six months ended June 30, 2017 and 2016, respectively; the Condensed Consolidated Statements of Stockholders' Equity and Cash Flows for the six months ended June 30, 2017; and other information disclosed in the related notes are unaudited. The Balance Sheet as of December 31, 2016, was derived from our audited consolidated financial statements as included in our 2016 Annual Report.

Use of Estimates and Assumptions

The preparation of the Financial Statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the related disclosure of contingent assets and liabilities at the date of the Financial Statements and the reported amounts of revenues and expenses during the reporting period. The more significant areas requiring the use of management estimates and assumptions relate to purchase price allocation for businesses acquired; mineral reserves that are the basis for future cash flow estimates utilized in impairment calculations and units-of-production amortization calculations; environmental, reclamation and closure obligations; estimates of recoverable minerals; estimates of allowance for doubtful accounts; estimates of fair value for certain reporting units and asset impairments (including impairments of goodwill and other long-lived assets); write-downs of inventory to net realizable value; equity-based compensation expense; post-employment, post-retirement and other employee benefit liabilities; valuation allowances for deferred tax assets; contingent considerations; reserves for contingencies and litigation and the fair value and accounting treatment of financial instruments including derivative instruments. We base our estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances. Accordingly, actual results may differ significantly from these estimates under different assumptions or conditions.

Recently Issued Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update (“ASU”)2014-09, Revenue from Contracts with Customers, which supersedes previous revenue recognition guidance. The new guidance introduces a new principles-based framework for revenue recognition and disclosure. Since its issuance, the FASB has issued an additional six ASUs, including ASU 2016-20 in December 2016, amending the guidance and the effective dates of amendments, and the SEC has rescinded certain related SEC guidance; the most recent of which was issued in May 2016. The pronouncements are effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within that reporting period. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. We have not yet completed our final review of the impact of this guidance, although we currently do not anticipate a material impact on our revenue recognition practices. In 2017, the Company identified a project team and commenced an initial impact assessment process for ASU 2014-09. To date, the Company has reviewed a sample of contracts with its customers and made preliminary assessments of the impact on revenue and expenses based on these reviews; however, the assessment of the impact to the Company’s results of operations, financial position and cash flows as a result of this guidance is ongoing. The Company will adopt this new standard as of January 1, 2018, and currently expects to apply the modified retrospective method, which may result in a cumulative effect adjustment as of the date of adoption. Both the Company’s initial assessment and its selected transition method may change depending on the results of the Company’s final assessment of the impact to its financial statements.

In January 2017, the FASB issued ASU 2017-04 Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment, which removes Step 2 from the goodwill impairment test. It is effective for annual and interim periods beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed with a measurement date after January 1, 2017. We are currently evaluating the impact of this accounting standard on our consolidated financial statements.

In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business ("ASU 2017-01"). The new guidance clarifies the definition of a business with the objective of adding guidance to assist companies and other reporting organizations with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The changes to the definition of a business will likely result in more acquisitions being accounted for as asset acquisitions. ASU 2017-01 is effective for annual periods beginning after December 15, 2017, including interim periods within those periods. Early application of the amendments in ASU 2017-01 is allowed for transactions for which the acquisition date occurs before the issuance date or effective date of the amendments, only when the transaction has not been reported in financial statements that have been issued or made available for issuance.

In March 2017, the FASB issued ASU 2017-07 Compensation-Retirement Benefits (Topic 715), Improving the Presentation of Net Periodic Pension Cost and Net Periodic Post-retirement Benefit ("ASU 2017-07"). ASU 2017-07 amends presentation requirements related to reporting the service cost component of net benefit costs to require that the service cost component be reported in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period, disaggregating the component from other net benefit costs. ASU 2017-07 also limits the components of net benefit cost eligible to be capitalized to service cost. ASU 2017-07 is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods for public business entities. We are currently evaluating the impact of this accounting standard on our consolidated financial statements.

In May 2017, the FASB issued ASU 2017-09 Compensation-Stock Compensation (Topic 718), Scope of Modification Accounting ("ASU 2017-09"). This Update amends the scope of modification for share-based payment arrangements. This ASU 2017-09 provides guidance on the types of the changes to the terms or conditions of share-based payments awards to which an entity would be required to apply modification accounting. Specifically, an entity would not apply modification accounting if the fair value, vesting conditions, and classification of the awards are the same immediately before and after the modification. ASU 2017-09 is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods for all entities. We are currently evaluating the impact of this accounting standard on our consolidated financial statements.