Supplemental Financial Information (Tables)

3 Months Ended

Mar. 31, 2023

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Schedule of Long Term Assets

The following table summarizes the components of Other long-term assets, net as presented in the Condensed Consolidated Balance Sheets:

	As of
(in thousands)	March 31, 2023		December 31, 2022
Other long-term assets, net:
Right of use assets, operating leases, net	$	10,122	$	7,734
Intangible assets, net	8,424		847
Spare parts, net	7,444		6,789
Upfront Customer Consideration	6,348		6,475
Mine development costs, net	5,657		5,478
Mine reclamation asset, net	1,616		1,641
Other	2,174		1,683
Total other long-term assets, net	$	41,785	$	30,647

Schedule of Other Liabilities

The following table details the components of Other current liabilities and Other long-term liabilities as presented in the Condensed Consolidated Balance Sheets:

	As of
(in thousands)	March 31, 2023		December 31, 2022
Other current liabilities:
Current portion of operating lease obligations	$	2,554	$	2,724
Income and other taxes payable	866		1,039
Current portion of mine reclamation liability	163		548
Other(1)	2,605		2,334
Total other current liabilities	$	6,188	$	6,645
Other long-term liabilities:
Operating lease obligations, long-term	$	7,642	$	5,133
Mine reclamation liabilities	5,259		7,985
Other	746		733
Total other long-term liabilities	$	13,647	$	13,851

(1) Included in Other current liabilities is $1.7 million related to the Repayment Agreement as defined in Note 10.

Schedule of Change in Asset Retirement Obligation

The Mine reclamation liabilities represent AROs and changes for the three months ended March 31, 2023 and year ended December 31, 2022 were as follows:

	As of
(in thousands)	March 31, 2023		December 31, 2022
Asset retirement obligations, beginning of period	$	8,533	$	9,959
Asset retirement obligations assumed(1)	1,500		—
Accretion	168		611
Liabilities settled(2)	(4,779)		(2,071)
Changes due to scope and timing of reclamation	—		34
Asset retirement obligations, end of period	5,422		8,533
Less current portion	163		548
Asset retirement obligations, long-term	$	5,259	$	7,985

(1) Represents two asset retirement obligations assumed as part of the Arq Acquisition; $0.5 million related to Corbin ARO and $1.0 million related to Mine 4 ARO.

(2) Represent the removal of the Marshall Mine ARO as a result of the MM Transaction as further discussed in Note 3.

Schedule of "Interest expense" in the Condensed Consolidated Statement of Operations

The following table details the components of "Interest expense" in the Condensed Consolidated Statement of Operations:

	Three Months Ended March 31,
(in thousands)	2023		2022
Interest on Term Loan	$	261	$	—
Interest on Arq Loan	98		—
Amortization of debt discounts and debt issuance costs	94		—
Other	81		86
	$	534	$	86