Revenue Revenue

12 Months Ended

Dec. 31, 2020

Revenue from Contract with Customer [Abstract]

Revenue

Contract Balances

The timing of revenue recognition, billings and cash collections results in billed accounts receivable, unbilled receivables and deferred revenue and advance payments from customers on the Consolidated Balance Sheets. Contract assets and liabilities are reported on a contract-by-contract basis. The Company had no material deferred contract costs recorded on the Consolidated Balance Sheets as of December 31, 2020 and 2019.

Note 2.    Revenue - (Continued)

Contract Balances - (Continued)

Contract assets: The Company recognizes unbilled receivables as contract assets when the Company has rights to consideration for work completed but has not yet billed at the reporting date. Unbilled receivables are included within accounts receivable, net on the Consolidated Balance Sheets. The balance of unbilled receivables as of December 31, 2020 and 2019 were $45.0 million and $9.4 million, respectively.

Contract Liabilities: The Company records contract liabilities when cash payments are received or due in advance of the Company's performance. Contract liabilities include deferred revenue and advance payments from customers. Contract liabilities are classified as either current or long-term in the Consolidated Balance Sheets based on the timing of when the Company expects to recognize revenue. As of December 31, 2020 and 2019, the contract liability balances totaled $48.8 million and $69.1 million, respectively. These balances included amounts classified as long-term as of December 31, 2020 and 2019 which were of $12.0 million and of $12.5 million, respectively, and are included within other long-term liabilities in the accompanying Consolidated Balance Sheets. Approximately $44.2 million of revenue recognized during the twelve month period ended December 31, 2020 was included in the combined contract liability balances as of December 31, 2019.

Remaining Performance Obligations

Remaining performance obligations represent the aggregate transaction price allocated to performance obligations with an original contract term greater than one year which are fully or partially unsatisfied at the end of the period. While the remaining performance obligation disclosure is similar in concept to backlog, the definition of remaining performance obligations excludes contracts that provide the customer with the right to cancel or terminate for convenience with no substantial penalty, even if historical experience indicates the likelihood of cancellation or termination is remote. The Company has elected to exclude contracts with customers with an original term of one year or less from remaining performance obligations while these contracts are included within backlog.

As of December 31, 2020, the aggregate amount of the transaction price allocated to remaining performance obligations was approximately $313.1 million. The Company expects to recognize revenue on a majority of the remaining performance obligations over the next twelve months.