Revenue Recognition

Nature of Performance Obligations

At contract inception, the Company assesses the goods and services promised in its contracts with customers and identifies a performance obligation for each promised good or service that is distinct. To identify the performance obligations, the Company considers all of the goods or services promised in the contract regardless of whether they are explicitly stated or are implied by customary business practices.

Each mine or mine area has a contract with its respective customer that represents a contract under ASC 606. For its consolidated entities, the Company’s performance obligations vary by contract and consist of the following:

At MLMC, each MMBtu delivered during the production period is considered a separate performance obligation. Revenue is recognized at the point in time that control of each MMBtu of lignite transfers to the customer. Fluctuations in revenue from period to period generally result from changes in customer demand.

At NAMining entities, the management service to oversee the operation of the equipment and delivery of limestone is the performance obligation accounted for as a series. Performance momentarily creates an asset that the customer simultaneously receives and consumes; therefore, control is transferred to the customer over time. Consistent with the conclusion that the customer simultaneously receives and consumes the benefits provided, an input-based measure of progress is appropriate. As each month of service is completed, revenue is recognized for the amount of actual costs incurred, plus the management fee and the general and administrative fee (as applicable). Fluctuations in revenue from period to period result from changes in customer demand and variances in reimbursable costs primarily due to increases and decreases in activity levels on individual contracts.

The Company enters into royalty contracts which grant the right to explore, develop, produce and sell minerals controlled by the Company. These arrangements result in the transfer of mineral rights for a period of time; however, no rights to the actual land are granted other than access for purposes of exploration, development, production and sales. The mineral rights revert back to the Company at the expiration of the contract.

Under these royalty contracts, granting exclusive right, title, and interest in and to minerals, if any, is the performance obligation. The performance obligation under these contracts represents a series of distinct goods or services whereby each day of access that is provided is distinct. The transaction price consists of a variable sales-based royalty and, in certain arrangements, a fixed component in the form of an up-front lease bonus payment. As the amount of consideration the Company will ultimately be entitled to is entirely susceptible to factors outside its control, the entire amount of variable consideration is constrained at contract inception. The fixed portion of the transaction price is recognized over the primary term of the contract, which is generally five years.

Significant Judgments

The Company’s contracts with its customers contain different types of variable consideration including, but not limited to, management fees that adjust based on coal volumes or MMBtu delivered or limestone tons, however, the terms of these variable payments relate specifically to our efforts to satisfy one or more, but not all of, the performance obligations (or to a specific outcome from satisfying the performance obligations), in the contract. Therefore, the Company allocates each variable payment (and subsequent changes to that payment) entirely to the specific performance obligation to which it relates. Management fees, as well as general and administrative fees, are also adjusted based on changes in specified indices (e.g., CPI) to compensate for general inflation changes. Index adjustments, if applicable, are effective prospectively. Certain contracts include reimbursement of actual costs incurred.

Disaggregation of Revenue

In accordance with ASC 606-10-50, the Company disaggregates revenue from contracts with customers into major goods and service lines and timing of transfer of goods and services. The Company determined that disaggregating revenue into these categories achieves the disclosure objective of depicting how the nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factors. The Company’s business consists of the Coal Mining, NAMining and Minerals Management segments as well as Unallocated Items. See Note 15 to the Consolidated Financial Statements for further discussion of segment reporting.

The following table disaggregates revenue by major sources for the years ended December 31:



Major Goods/Service Lines	2019			2018
Coal Mining	$	68,701		$	81,549
NAMining	42,823			36,950
Minerals Management	30,119			17,352
Unallocated Items	790			665
Eliminations	(1,443		)	(1,141		)
Total revenues	$	140,990		$	135,375

Timing of Revenue Recognition
Goods transferred at a point in time	$	66,102		$	78,849
Services transferred over time	74,888			56,526
Total revenues	$	140,990		$	135,375

Contract Balances

The opening and closing balances of the Company’s current and long-term contract liabilities and receivables are as follows:



	Contract balances
	Trade accounts receivable, net			Contract liability (current)		Contract liability (long-term)
Balance, January 1, 2019	$	20,817		$	754	$	2,008
Balance, December 31, 2019	15,444			944		2,153
Increase (decrease)	$	(5,373	)	$	190	$	145

As described above, the Company enters into royalty contracts that grant exclusive right, title, and interest in and to minerals. The transaction price consists of a variable sales-based royalty and, in certain arrangements, a fixed component in the form of an up-front lease bonus payment. The timing of the payment of the fixed portion of the transaction price is upfront, however, the performance obligation is satisfied over the primary term of the contract, which is generally five years. Therefore, at the time any such up-front payment is received, a contract liability is recorded which represents deferred revenue. The difference between the opening and closing balance of this contract liability, which is shown above, primarily results from the difference between new lease bonus payments received and amortization of up-front lease bonus payments received in previous periods.

The amount of revenue recognized in the years ended December 31, 2019 and December 31, 2018 that was included in the opening contract liability was $0.9 million and $1.2 million, respectively. This revenue consists of up-front lease bonus payments received under royalty contracts that are recognized over the primary term of the royalty contracts, which are generally five years. The Company expects to recognize $0.9 million in both 2020 and 2021, $0.7 million in 2022, $0.3 million in 2023, and $0.1 million in 2024 related to the contract liability remaining at December 31, 2019. The difference between the opening and closing balances of the Company’s accounts receivable and contract liabilities results from the timing difference between the Company’s performance and the customer’s payment. Contracts with payments in arrears are recognized as receivables.

The Company has no contract assets recognized from the costs to obtain or fulfill a contract with a customer.