Summary Of Significant Accounting Policies	3 Months Ended
Mar. 31, 2019
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Significant Accounting Policies Please see Note 2 -- Summary of Significant Accounting Policies contained in the 2018 10-K. Leases On January 1, 2019, the Company adopted Accounting Standards Codification (“ASC”) 842, Leases. Changes to the Company’s accounting policy as a result of adoption are discussed below. From time to time, the Company enters into contractual agreements to lease mining equipment and facilities. Based upon the Company’s assessment of the terms of a specific lease agreement, the Company will classify a lease as either finance or operating. Right-of-use (“ROU”) assets and lease liabilities related to finance leases are presented in Property, plant and equipment, net and Debt on the Condensed Consolidated Balance Sheet. ROU assets and lease liabilities related to operating leases that are subject to the ASC 842 measurement requirements such as operating leases with lease terms greater than twelve months are presented in Other asset, non-current, Accrued liabilities and other, and Other long-term liabilities on the Condensed Consolidated Balance Sheet. Operating and finance lease ROU assets and lease liabilities are recognized at the commencement date based on the present value of the future lease payments over the lease term. The discount rate used to determine the present value of the lease payments, is the rate implicit in the lease unless that rate cannot be readily determined, in that case, the Company utilizes its incremental borrowing rate in determining the present value of the future lease payments. The incremental borrowing rate is the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and amount equal to the lease payments in a similar economic environment. Operating lease ROU assets may also include any cumulative prepaid or accrued rent when the lease payments are uneven throughout the lease term. The ROU assets and lease liabilities may also include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. The ROU asset includes any lease payments made and lease incentives received prior to the commencement date. The Company has lease arrangements with lease and non-lease components which are accounted for separately. Non-lease components of the lease payments are expenses as incurred and are not included in determining the present value. Accounting Standards Issued and Implemented In February 2016, the FASB issued ASU 2016-02, “Leases,” which requires lessees to recognize assets and liabilities for the rights and obligations created by most leases on the balance sheet. These changes became effective for the Company’s fiscal year beginning January 1, 2019 and the Company adopted it using the cumulative-effect adjustment transition method approved by the FASB in July 2018, which does not require the Company to recast the comparative periods presented when transitioning to the new guidance on January 1, 2019. The Company elected to utilize the transition related practical expedients permitted by the new standard. In addition to existing finance leases and other financing obligations, the adoption of the new standard resulted in the recognition of additional ROU assets and lease liabilities related to operating leases of approximately $65.0 million. There was no material impact to the Consolidated Statements of Comprehensive Income (Loss) or the Consolidated Statements of Cash Flows or an impact on the Company’s debt covenant calculations as a result of the adoption of ASU 2016-02. See Note 7 -- Leases for additional qualitative and quantitative disclosures related to leasing arrangements.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Significant Accounting Policies

Please see Note 2 -- Summary of Significant Accounting Policies contained in the 2018 10-K.

Leases

On January 1, 2019, the Company adopted Accounting Standards Codification (“ASC”) 842, Leases. Changes to the Company’s accounting policy as a result of adoption are discussed below.

From time to time, the Company enters into contractual agreements to lease mining equipment and facilities. Based upon the Company’s assessment of the terms of a specific lease agreement, the Company will classify a lease as either finance or operating. Right-of-use (“ROU”) assets and lease liabilities related to finance leases are presented in Property, plant and equipment, net and Debt on the Condensed Consolidated Balance Sheet. ROU assets and lease liabilities related to operating leases that are subject to the ASC 842 measurement requirements such as operating leases with lease terms greater than twelve months are presented in Other asset, non-current, Accrued liabilities and other, and Other long-term liabilities on the Condensed Consolidated Balance Sheet.

Operating and finance lease ROU assets and lease liabilities are recognized at the commencement date based on the present value of the future lease payments over the lease term. The discount rate used to determine the present value of the lease payments, is the rate implicit in the lease unless that rate cannot be readily determined, in that case, the Company utilizes its incremental borrowing rate in determining the present value of the future lease payments. The incremental borrowing rate is the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and amount equal to the lease payments in a similar economic environment. Operating lease ROU assets may also include any cumulative prepaid or accrued rent when the lease payments are uneven throughout the lease term. The ROU assets and lease liabilities may also include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. The ROU asset includes any lease payments made and lease incentives received prior to the commencement date. The Company has lease arrangements with lease and non-lease components which are accounted for separately. Non-lease components of the lease payments are expenses as incurred and are not included in determining the present value.

Accounting Standards Issued and Implemented

In February 2016, the FASB issued ASU 2016-02, “Leases,” which requires lessees to recognize assets and liabilities for the rights and obligations created by most leases on the balance sheet. These changes became effective for the Company’s fiscal year beginning January 1, 2019 and the Company adopted it using the cumulative-effect adjustment transition method approved by the FASB in July 2018, which does not require the Company to recast the comparative periods presented when transitioning to the new guidance on January 1, 2019. The Company elected to utilize the transition related practical expedients permitted by the new standard. In addition to existing finance leases and other financing obligations, the adoption of the new standard resulted in the recognition of additional ROU assets and lease liabilities related to operating leases of approximately $65.0 million. There was no material impact to the Consolidated Statements of Comprehensive Income (Loss) or the Consolidated Statements of Cash Flows or an impact on the Company’s debt covenant calculations as a result of the adoption of ASU 2016-02. See Note 7 -- Leases for additional qualitative and quantitative disclosures related to leasing arrangements.