Note 2 - Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2019
Notes to Financial Statements
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	NOTE 2—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation—These interim financial statements are unaudited and have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Certain disclosures have been condensed or omitted from these financial statements. Accordingly, they do not include all the information and notes required by accounting principles generally accepted in the United States of America (“GAAP”) for complete consolidated financial statements, and should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Annual Report on Form 10‑K for the year ended December 31, 2018. In the opinion of management, the accompanying unaudited condensed consolidated financial statements include all adjustments, consisting of normal recurring adjustments, necessary to fairly present the financial position as of, and the results of operations for, all periods presented. In preparing the accompanying financial statements, management has made certain estimates and assumptions that affect reported amounts in the condensed consolidated financial statements and disclosures of contingencies. Actual results may differ from those estimates. The results for interim periods are not necessarily indicative of annual results. Certain reclassifications have been made to the prior period’s consolidated financial statements and related footnotes to conform them to the current period presentation. Revenue Recognition—Our primary source of revenue is from the sale of coal through contracts with steel and coke producers usually having durations of one year or less. In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014‑09, Revenue from Contracts with Customers. This new standard supersedes nearly all existing revenue recognition guidance under GAAP. The core principle of ASU 2014‑09 is to recognize revenues in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. We adopted ASU 2014‑09, Revenue from Contracts with Customers, on January 1, 2018 using the modified retrospective method. Before adoption of the new standard, revenue was recognized when risk of loss passed to our customer. The timing of revenue recognition for our coal sales remained consistent between the new and previous standards. There was no material impact on our consolidated financial statements from adopting the new standard but we have expanded disclosure about our revenues. For periods subsequent to January 1, 2018, revenue is recognized when performance obligations under the terms of a contract with our customers are satisfied. This occurs when control of the coal is transferred to our customers. For coal shipments to domestic customers via rail or truck, control is generally transferred when the railcar or truck is loaded. Control is transferred for export coal shipments to customers via ocean vessel when the vessel is loaded at the port. Our coal sales generally include up to 90‑day payment terms following the transfer of control of the goods to our customer. In the case of some of our foreign customers, our contracts also require that letters of credit are posted to secure payment of any outstanding receivable to the Company. We do not include extended payment terms in our contracts. Our contracts with customers typically provide for minimum specifications or qualities of the coal we deliver. Variances from these specifications or qualities are settled by means of price adjustments. Generally, these price adjustments are settled within 30 days of delivery and are insignificant. Earnings per Share—Basic earnings per share is calculated using our weighted-average outstanding common shares. Diluted earnings per share is calculated using our weighted-average outstanding common shares including the dilutive effect of stock option awards as determined under the treasury stock method. Financial Instruments—Our financial assets and liabilities consist of cash, accounts receivable, accounts payable and notes payable. The fair values of these instruments approximate their carrying amounts at each reporting date. We invested excess cash amounts before its planned expenditure for capital projects in highly-rated securities with the primary objective of achieving competitive low risk interest rate return, while minimizing the potential risk of principal loss. Fair values were determined for each individual security based on observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the securities. The difference between the carrying amount and fair value of these securities was not material. Nonrecurring fair value measurements include asset retirement obligations, the estimated fair value of which is calculated as the present value of estimated cash flows related to its reclamation liabilities using Level 3 inputs. The significant inputs used to calculate such liabilities include estimates of costs to be incurred, the Company’s credit adjusted discount rate, inflation rates and estimated date of reclamation. Concentrations—During the three and six months ended June 30, 2019, sales to four customers accounted for approximately 55% of total revenue in each period. The total balance due from these four customers at June 30, 2019 was approximately 69% of total accounts receivable. During the three and six months ended June 30, 2018 sales to three customers accounted for approximately 79% and 75% of total revenue, respectively. Recent Accounting Pronouncements—In February 2016, the FASB issued ASU 2016‑02, Leases, which aims to make leasing activities more transparent and comparable and requires substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. Leases of mineral reserves and related land leases have been exempted from the standard. We adopted ASU 2016‑02, Leases, on January 1, 2019. The Company elected the “package of practical expedients” within the standard which permits the Company not to reassess its prior conclusions about lease identification, lease classification and initial direct costs. The Company made an accounting policy election to not separate lease and non-lease components for all leases. The adoption of this standard resulted in the recognition of right-of-use assets and lease liabilities of $0.3 million, which were not previously recorded on the Company’s balance sheet.

NOTE 2—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation—These interim financial statements are unaudited and have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Certain disclosures have been condensed or omitted from these financial statements. Accordingly, they do not include all the information and notes required by accounting principles generally accepted in the United States of America (“GAAP”) for complete consolidated financial statements, and should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Annual Report on Form 10‑K for the year ended December 31, 2018.

In the opinion of management, the accompanying unaudited condensed consolidated financial statements include all adjustments, consisting of normal recurring adjustments, necessary to fairly present the financial position as of, and the results of operations for, all periods presented. In preparing the accompanying financial statements, management has made certain estimates and assumptions that affect reported amounts in the condensed consolidated financial statements and disclosures of contingencies. Actual results may differ from those estimates. The results for interim periods are not necessarily indicative of annual results. Certain reclassifications have been made to the prior period’s consolidated financial statements and related footnotes to conform them to the current period presentation.

Revenue Recognition—Our primary source of revenue is from the sale of coal through contracts with steel and coke producers usually having durations of one year or less. In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014‑09, Revenue from Contracts with Customers. This new standard supersedes nearly all existing revenue recognition guidance under GAAP. The core principle of ASU 2014‑09 is to recognize revenues in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. We adopted ASU 2014‑09, Revenue from Contracts with Customers, on January 1, 2018 using the modified retrospective method. Before adoption of the new standard, revenue was recognized when risk of loss passed to our customer. The timing of revenue recognition for our coal sales remained consistent between the new and previous standards. There was no material impact on our consolidated financial statements from adopting the new standard but we have expanded disclosure about our revenues.

For periods subsequent to January 1, 2018, revenue is recognized when performance obligations under the terms of a contract with our customers are satisfied. This occurs when control of the coal is transferred to our customers. For coal shipments to domestic customers via rail or truck, control is generally transferred when the railcar or truck is loaded. Control is transferred for export coal shipments to customers via ocean vessel when the vessel is loaded at the port.

Our coal sales generally include up to 90‑day payment terms following the transfer of control of the goods to our customer. In the case of some of our foreign customers, our contracts also require that letters of credit are posted to secure payment of any outstanding receivable to the Company. We do not include extended payment terms in our contracts. Our contracts with customers typically provide for minimum specifications or qualities of the coal we deliver. Variances from these specifications or qualities are settled by means of price adjustments. Generally, these price adjustments are settled within 30 days of delivery and are insignificant.

Earnings per Share—Basic earnings per share is calculated using our weighted-average outstanding common shares. Diluted earnings per share is calculated using our weighted-average outstanding common shares including the dilutive effect of stock option awards as determined under the treasury stock method.

Financial Instruments—Our financial assets and liabilities consist of cash, accounts receivable, accounts payable and notes payable. The fair values of these instruments approximate their carrying amounts at each reporting date.

We invested excess cash amounts before its planned expenditure for capital projects in highly-rated securities with the primary objective of achieving competitive low risk interest rate return, while minimizing the potential risk of principal loss. Fair values were determined for each individual security based on observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the securities. The difference between the carrying amount and fair value of these securities was not material.

Nonrecurring fair value measurements include asset retirement obligations, the estimated fair value of which is calculated as the present value of estimated cash flows related to its reclamation liabilities using Level 3 inputs. The significant inputs used to calculate such liabilities include estimates of costs to be incurred, the Company’s credit adjusted discount rate, inflation rates and estimated date of reclamation.

Concentrations—During the three and six months ended June 30, 2019, sales to four customers accounted for approximately 55% of total revenue in each period. The total balance due from these four customers at June 30, 2019 was approximately 69% of total accounts receivable. During the three and six months ended June 30, 2018 sales to three customers accounted for approximately 79% and 75% of total revenue, respectively.

Recent Accounting Pronouncements—In February 2016, the FASB issued ASU 2016‑02, Leases, which aims to make leasing activities more transparent and comparable and requires substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. Leases of mineral reserves and related land leases have been exempted from the standard. We adopted ASU 2016‑02, Leases, on January 1, 2019. The Company elected the “package of practical expedients” within the standard which permits the Company not to reassess its prior conclusions about lease identification, lease classification and initial direct costs. The Company made an accounting policy election to not separate lease and non-lease components for all leases. The adoption of this standard resulted in the recognition of right-of-use assets and lease liabilities of $0.3 million, which were not previously recorded on the Company’s balance sheet.