SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) subsidiary shares	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Accounting Policies
Number of wholly-owned subsidiaries | subsidiary	63
Other comprehensive income (loss), net of tax	$ 518,000	$ (798,000)	$ 0
Accounts receivable, net	628,700,000	585,500,000
Accounts receivable, allowance for losses	$ 22,829,000	14,761,000	12,086,000
Sales commission, renewal period (in years)	1 year
Research and development expense	$ 109,585,000	105,184,000	93,481,000
Goodwill	2,532,109,000	2,489,308,000	2,359,674,000
Impairments of intangible assets	0	0	0
Impairments of long-lived assets	0	0	0
Capitalized post acquisition software development costs	32,500,000	27,600,000	21,700,000
Cash and cash equivalents	165,493,000	173,857,000	$ 309,171,000	$ 603,623,000
Case Management, Business Process Management, Data And Insight
Accounting Policies
Goodwill	$ 1,700,000,000
Percentage of total goodwill	67.00%
Stock Option Plan
Accounting Policies
Share based compensation contractual term (in years)	10 years
Stock Option Plan | 2018 Plan
Accounting Policies
Share based compensation contractual term (in years)	10 years
Performance Shares | 2018 Plan
Accounting Policies
Share conversion rate (in shares) | shares	1
Unbilled Revenues
Accounting Policies
Accounts receivable, net	$ 119,200,000	135,400,000
Unbilled Revenues | Retention Receivable
Accounting Policies
Accounts receivable, net	$ 9,800,000	$ 8,600,000
Minimum
Accounting Policies
Contract term (in years)	1 year
Typical contract term (in years)	3 years
Progress billing retention percentage	5.00%
Payment term	30 days
Sales commissions amortization period (in years)	3 years
Minimum | Software and Software Development Costs
Accounting Policies
Remaining estimated economic life (in years)	3 years
Minimum | 2018 Plan
Accounting Policies
Share based compensation vesting period (in years)	3 years
Minimum | Stock Option Plan
Accounting Policies
Share based compensation vesting period (in years)	3 years
Minimum | Restricted Stock Units (RSUs) | 2018 Plan
Accounting Policies
Share based compensation vesting period (in years)	3 years
Minimum | Performance Shares | 2018 Plan
Accounting Policies
Share based compensation vesting period (in years)	1 year
Maximum
Accounting Policies
Contract term (in years)	10 years
Typical contract term (in years)	5 years
Progress billing retention percentage	15.00%
Payment term	90 days
Sales commissions amortization period (in years)	7 years
Maximum | Software and Software Development Costs
Accounting Policies
Remaining estimated economic life (in years)	5 years
Maximum | 2018 Plan
Accounting Policies
Share based compensation vesting period (in years)	5 years
Maximum | Stock Option Plan
Accounting Policies
Share based compensation vesting period (in years)	5 years
Maximum | Restricted Stock Units (RSUs) | 2018 Plan
Accounting Policies
Share based compensation vesting period (in years)	5 years
Maximum | Performance Shares | 2018 Plan
Accounting Policies
Share based compensation vesting period (in years)	3 years
SaaS arrangements services | Minimum
Accounting Policies
Contract term (in years)	1 year
Typical contract term (in years)	3 years
SaaS arrangements services | Maximum
Accounting Policies
Contract term (in years)	10 years
Typical contract term (in years)	5 years