Accounting Standards and Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2021
Accounting Policies [Abstract]
Use of Estimates	USE OF ESTIMATES The preparation of our financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include revenue recognition, determining the nature and timing of satisfaction of performance obligations, determining the standalone selling price (“SSP”) of performance obligations, variable consideration, and other obligations such as returns and refunds; loss contingencies; the estimated useful life of deferred commissions; the carrying amount of goodwill; the carrying amount and estimated useful lives of intangible assets; the carrying amount of operating lease right-of-use assets and operating lease liabilities; determining share-based compensation expense; the valuation allowance for receivables; and determining the potential outcome of future tax consequences of events that have been recognized on our consolidated financial statements or tax returns. Actual results could differ from estimates.
Revenue Recognition	REVENUE RECOGNITION Nature of Products and Services: We earn revenue from software licenses, royalties, subscription-based services, software services, post-contract customer support (“PCS” or “maintenance”), hardware, and appraisal services. Revenue is recognized upon transfer of control of promised products or services to customers in an amount that reflects the consideration we expect to receive in exchange for those products and services. We determine revenue recognition through the following steps: •Identification of the contract, or contracts with a customer •Identification of the performance obligations in the contract •Determination of the transaction price •Allocation of the transaction price to the performance obligations in the contract •Recognition of revenue when, or as, we satisfy a performance obligation Most of our software arrangements with customers contain multiple performance obligations that range from software licenses, installation, training, and consulting to software modification and customization to meet specific customer needs (services), hosting, and PCS. For these contracts, we account for individual performance obligations separately when they are distinct. We evaluate whether separate performance obligations can be distinct or should be accounted for as one performance obligation. Arrangements that include software services, such as training or installation, are evaluated to determine whether the customer can benefit from the services either on their own or together with other resources readily available to the customer and whether the services are separately identifiable from other promises in the contract. The transaction price is allocated to the distinct performance obligations on a relative SSP basis. We determine the SSP based on our overall pricing objectives, taking into consideration market conditions and other factors, including the value of our contracts, the applications sold, customer demographics, and the number and types of users within our contracts. Revenue is recognized net of allowances for sales adjustments and any taxes collected from customers, which are subsequently remitted to governmental authorities. Significant Judgments: Our contracts with customers often include multiple performance obligations to a customer. When a software arrangement (license or subscription) includes both software licenses and software services, judgment is required to determine whether the software license is considered distinct and accounted for separately, or not distinct and accounted for together with the software services and recognized over time. The transaction price is allocated to the separate performance obligations on a relative SSP basis. We determine the SSP based on our overall pricing objectives, taking into consideration market conditions and other factors, including the value of our contracts, the applications sold, customer demographics, and the number and types of users within our contracts. We use a range of amounts to estimate SSP when we sell each of the products and services separately and need to determine whether there is a discount to be allocated based on the relative SSP of the various products and services. In instances where SSP is not directly observable, such as when we do not sell the product or service separately, we determine SSP using the expected cost-plus margin approach. For arrangements that involve significant production, modification or customization of the software, or where software services otherwise cannot be considered distinct, we recognize revenue as control is transferred to the customer over time using progress-to-completion methods. Depending on the contract, we measure progress-to-completion primarily using labor hours incurred, or value added. The progress-to-completion method generally results in the recognition of reasonably consistent profit margins over the life of a contract because we can provide reasonably dependable estimates of contract billings and contract costs. We use the level of profit margin that is most likely to occur on a contract. If the most likely profit margin cannot be precisely determined, the lowest probable level of profit margin in the range of estimates is used until the results can be estimated more precisely. These arrangements are often implemented over an extended time period and occasionally require us to revise total cost estimates. Amounts recognized in revenue are calculated using the progress-to-completion measurement after giving effect to any changes in our cost estimates. Changes to total estimated contract costs, if any, are recorded in the period they are determined. Estimated losses on uncompleted contracts are recorded in the period in which we first determine that a loss is apparent. For e-filing transaction fees and transaction-based revenues from digital government services and online payments, we have the right to charge the customer an amount that directly corresponds with the value to the customer of our performance to date. Therefore, we recognize revenue for these services over time based on the amount billable to the customer in accordance with the 'as invoiced' practical expedient in ASC 606-10-55-18. In some cases, we are paid on a fixed fee basis and recognize the revenue ratably over the contractual period. Typically, the structure of our arrangements does not give rise to variable consideration. However, in those instances whereby variable consideration exists, we include in our estimates, additional revenue for variable consideration when we believe we have an enforceable right, the amount can be estimated reliably and its realization is probable. Contract Balances: Accounts receivable and allowance for losses and sales adjustments Timing of revenue recognition may differ from the timing of invoicing to customers. We record an unbilled receivable when revenue is recognized prior to invoicing, or deferred revenue when invoicing occurs prior to recognizing revenue. For multi-year agreements, we generally invoice customers annually at the beginning of each annual coverage period. We record an unbilled receivable related to revenue recognized for on-premises licenses as we have an unconditional right to invoice and receive payment in the future related to those licenses. At September 30, 2021, and December 31, 2020, total current and long-term accounts receivable, net of allowance for losses and sales adjustments, was $553.0 million and $403.7 million, respectively. We have recorded unbilled receivables of $147.4 million and $140.8 million at September 30, 2021 and December 31, 2020, respectively. Included in unbilled receivables are retention receivables of $8.2 million and $13.1 million at September 30, 2021 and December 31, 2020, respectively, which become payable upon the completion of the contract or completion of our fieldwork and formal hearings. Unbilled receivables expected to be collected within one year have been included with accounts receivable, current portion in the accompanying condensed consolidated balance sheets. Unbilled receivables and retention receivables expected to be collected past one year have been included with accounts receivable, long-term portion in the accompanying condensed consolidated balance sheets. We maintain allowances for losses and sales adjustments, which losses are recorded against revenue at the time the loss is incurred. Since most of our clients are domestic governmental entities, we rarely incur a credit loss resulting from the inability of a client to make required payments. Events or changes in circumstances that indicate the carrying amount for the allowances for losses and sales adjustments may require revision, include, but are not limited to, managing our client’s expectations regarding the scope of the services to be delivered and defects or errors in new versions or enhancements of our software products. Our allowance for losses and sales adjustments of $10.6 million and $9.3 million at September 30, 2021, and December 31, 2020, respectively, does not include provisions for credit losses.
Goodwill	GoodwillWe assess goodwill for impairment annually, or more frequently whenever events or changes in circumstances indicate its carrying value may not be recoverable. We begin with the qualitative assessment of whether it is more likely than not that a reporting unit's fair value is less than its carrying value before applying the quantitative assessment described below. If it is determined through the evaluation of events or circumstances that the carrying value may not be recoverable, we perform a comparison of the estimated fair value of the reporting unit to which the goodwill has been assigned to the sum of the carrying value of the assets and liabilities of that unit. If the sum of the carrying value of the assets and liabilities of a reporting unit exceeds the estimated fair value of that reporting unit, the carrying value of the reporting unit's goodwill is reduced to its fair value through an adjustment to the goodwill balance, resulting in an impairment charge. The fair values calculated in our impairment tests are determined using discounted cash flow models involving several assumptions (Level 3 inputs). The assumptions that are used are based upon what we believe a hypothetical marketplace participant would use in estimating fair value. We evaluate the reasonableness of the fair value calculations of our reporting units by comparing the total of the fair value of all of our reporting units to our total market capitalization.
Recently Adopted/Issued Accounting Pronouncements	RECENTLY ADOPTED ACCOUNTING PRONOUNCEMENTS In August 2020, the FASB issued ASU 2020-06, which simplifies the accounting for convertible instruments by removing the separation models for (1) convertible debt with a cash conversion feature and (2) convertible instruments with a beneficial conversion feature. As a result, a convertible debt instrument will be accounted for as a single liability measured at its amortized cost. These changes will reduce reported interest expense and increase reported net income for entities that have issued a convertible instrument that was bifurcated according to previously existing rules. ASU 2020-06 also requires the application of the if-converted method for calculating diluted earnings per share and the treasury stock method will be no longer available. This standard will be effective for the Company’s fiscal years beginning in the first quarter of 2022, with early adoption permitted. The Company has elected to early adopt this standard as of January 1, 2021. Our accounting and disclosures related to our convertible senior notes issued on March 9, 2021, reflect the requirements of this standard. For further information, please refer to Note 7, Debt. In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes, (“ASU 2019-12”) which simplifies the accounting for income taxes, eliminates certain exceptions within ASC 740, Income Taxes, and clarifies certain aspects of the current guidance to promote consistency among reporting entities. The new standard is effective for fiscal years beginning after December 15, 2020. We adopted ASU 2019-12 as of January 1, 2021. The adoption of this standard did not have a material impact on our consolidated financial statements.

Accounting Standards and Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2021

USE OF ESTIMATES

The preparation of our financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include revenue recognition, determining the nature and timing of satisfaction of performance obligations, determining the standalone selling price (“SSP”) of performance obligations, variable consideration, and other obligations such as returns and refunds; loss contingencies; the estimated useful life of deferred commissions; the carrying amount of goodwill; the carrying amount and estimated useful lives of intangible assets; the carrying amount of operating lease right-of-use assets and operating lease liabilities; determining share-based compensation expense; the valuation allowance for receivables; and determining the potential outcome of future tax consequences of events that have been recognized on our consolidated financial statements or tax returns. Actual results could differ from estimates.

Revenue Recognition

REVENUE RECOGNITION

Nature of Products and Services:

We earn revenue from software licenses, royalties, subscription-based services, software services, post-contract customer support (“PCS” or “maintenance”), hardware, and appraisal services. Revenue is recognized upon transfer of control of promised products or services to customers in an amount that reflects the consideration we expect to receive in exchange for those products and services. We determine revenue recognition through the following steps:

•Identification of the contract, or contracts with a customer

•Identification of the performance obligations in the contract

•Determination of the transaction price

•Allocation of the transaction price to the performance obligations in the contract

•Recognition of revenue when, or as, we satisfy a performance obligation

Most of our software arrangements with customers contain multiple performance obligations that range from software licenses, installation, training, and consulting to software modification and customization to meet specific customer needs (services), hosting, and PCS. For these contracts, we account for individual performance obligations separately when they are distinct. We evaluate whether separate performance obligations can be distinct or should be accounted for as one performance obligation. Arrangements that include software services, such as training or installation, are evaluated to determine whether the customer can benefit from the services either on their own or together with other resources readily available to the customer and whether the services are separately identifiable from other promises in the contract. The transaction price is allocated to the distinct performance obligations on a relative SSP basis. We determine the SSP based on our overall pricing objectives, taking into consideration market conditions and other factors, including the value of our contracts, the applications sold, customer demographics, and the number and types of users within our contracts. Revenue is recognized net of allowances for sales adjustments and any taxes collected from customers, which are subsequently remitted to governmental authorities.

Significant Judgments:

Our contracts with customers often include multiple performance obligations to a customer. When a software arrangement (license or subscription) includes both software licenses and software services, judgment is required to determine whether the software license is considered distinct and accounted for separately, or not distinct and accounted for together with the software services and recognized over time.

The transaction price is allocated to the separate performance obligations on a relative SSP basis. We determine the SSP based on our overall pricing objectives, taking into consideration market conditions and other factors, including the value of our contracts, the applications sold, customer demographics, and the number and types of users within our contracts. We use a range of amounts to estimate SSP when we sell each of the products and services separately and need to determine whether there is a discount to be allocated based on the relative SSP of the various products and services. In instances where SSP is not directly observable, such as when we do not sell the product or service separately, we determine SSP using the expected cost-plus margin approach.

For arrangements that involve significant production, modification or customization of the software, or where software services otherwise cannot be considered distinct, we recognize revenue as control is transferred to the customer over time using progress-to-completion methods. Depending on the contract, we measure progress-to-completion primarily using labor hours incurred, or value added. The progress-to-completion method generally results in the recognition of reasonably consistent profit margins over the life of a contract because we can provide reasonably dependable estimates of contract billings and contract costs. We use the level of profit margin that is most likely to occur on a contract. If the most likely profit margin cannot be precisely determined, the lowest probable level of profit margin in the range of estimates is used until the results can be estimated more precisely. These arrangements are often implemented over an extended time period and occasionally require us to revise total cost estimates. Amounts recognized in revenue are calculated using the progress-to-completion measurement after giving effect to any changes in our cost estimates. Changes to total estimated contract costs, if any, are recorded in the period they are determined. Estimated losses on uncompleted contracts are recorded in the period in which we first determine that a loss is apparent.

For e-filing transaction fees and transaction-based revenues from digital government services and online payments, we have the right to charge the customer an amount that directly corresponds with the value to the customer of our performance to date. Therefore, we recognize revenue for these services over time based on the amount billable to the customer in accordance with the 'as invoiced' practical expedient in ASC 606-10-55-18. In some cases, we are paid on a fixed fee basis and recognize the revenue ratably over the contractual period. Typically, the structure of our arrangements does not give rise to variable consideration. However, in those instances whereby variable consideration exists, we include in our estimates, additional revenue for variable consideration when we believe we have an enforceable right, the amount can be estimated reliably and its realization is probable.

Contract Balances:

Accounts receivable and allowance for losses and sales adjustments

Timing of revenue recognition may differ from the timing of invoicing to customers. We record an unbilled receivable when revenue is recognized prior to invoicing, or deferred revenue when invoicing occurs prior to recognizing revenue. For multi-year agreements, we generally invoice customers annually at the beginning of each annual coverage period. We record an unbilled receivable related to revenue recognized for on-premises licenses as we have an unconditional right to invoice and receive payment in the future related to those licenses.

At September 30, 2021, and December 31, 2020, total current and long-term accounts receivable, net of allowance for losses and sales adjustments, was $553.0 million and $403.7 million, respectively. We have recorded unbilled receivables of $147.4 million and $140.8 million at September 30, 2021 and December 31, 2020, respectively. Included in unbilled receivables are retention receivables of $8.2 million and $13.1 million at September 30, 2021 and December 31, 2020, respectively, which become payable upon the completion of the contract or completion of our fieldwork and formal hearings. Unbilled receivables expected to be collected within one year have been included with accounts receivable, current portion in the accompanying condensed consolidated balance sheets. Unbilled receivables and retention receivables expected to be collected past one year have been included with accounts receivable, long-term portion in the accompanying condensed consolidated balance sheets.

We maintain allowances for losses and sales adjustments, which losses are recorded against revenue at the time the loss is incurred. Since most of our clients are domestic governmental entities, we rarely incur a credit loss resulting from the inability of a client to make required payments. Events or changes in circumstances that indicate the carrying amount for the allowances for losses and sales adjustments may require revision, include, but are not limited to, managing our client’s expectations regarding the scope of the services to be delivered and defects or errors in new versions or enhancements of our software products. Our allowance for losses and sales adjustments of $10.6 million and $9.3 million at September 30, 2021, and December 31, 2020, respectively, does not include provisions for credit losses.

Goodwill

GoodwillWe assess goodwill for impairment annually, or more frequently whenever events or changes in circumstances indicate its carrying value may not be recoverable. We begin with the qualitative assessment of whether it is more likely than not that a reporting unit's fair value is less than its carrying value before applying the quantitative assessment described below. If it is determined through the evaluation of events or circumstances that the carrying value may not be recoverable, we perform a comparison of the estimated fair value of the reporting unit to which the goodwill has been assigned to the sum of the carrying value of the assets and liabilities of that unit. If the sum of the carrying value of the assets and liabilities of a reporting unit exceeds the estimated fair value of that reporting unit, the carrying value of the reporting unit's goodwill is reduced to its fair value through an adjustment to the goodwill balance, resulting in an impairment charge. The fair values calculated in our impairment tests are determined using discounted cash flow models involving several assumptions (Level 3 inputs). The assumptions that are used are based upon what we believe a hypothetical marketplace participant would use in estimating fair value. We evaluate the reasonableness of the fair value calculations of our reporting units by comparing the total of the fair value of all of our reporting units to our total market capitalization.

Recently Adopted/Issued Accounting Pronouncements

RECENTLY ADOPTED ACCOUNTING PRONOUNCEMENTS

In August 2020, the FASB issued ASU 2020-06, which simplifies the accounting for convertible instruments by removing the separation models for (1) convertible debt with a cash conversion feature and (2) convertible instruments with a beneficial conversion feature. As a result, a convertible debt instrument will be accounted for as a single liability measured at its amortized cost. These changes will reduce reported interest expense and increase reported net income for entities that have issued a convertible instrument that was bifurcated according to previously existing rules. ASU 2020-06 also requires the application of the if-converted method for calculating diluted earnings per share and the treasury stock method will be no longer available. This standard will be effective for the Company’s fiscal years beginning in the first quarter of 2022, with early adoption permitted. The Company has elected to early adopt this standard as of January 1, 2021. Our accounting and disclosures related to our convertible senior notes issued on March 9, 2021, reflect the requirements of this standard. For further information, please refer to Note 7, Debt.

In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes, (“ASU 2019-12”) which simplifies the accounting for income taxes, eliminates certain exceptions within ASC 740, Income Taxes, and clarifies certain aspects of the current guidance to promote consistency among reporting entities. The new standard is effective for fiscal years beginning after December 15, 2020. We adopted ASU 2019-12 as of January 1, 2021. The adoption of this standard did not have a material impact on our consolidated financial statements.