Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Significant Accounting Policies [Line Items]
Interest income		$ 0	$ 200	$ 400
Sales allowance, billing-related adjustments		600	800
Prepaid implementation costs		400	0
Capitalized implementation costs		3,187	826
Outstanding standby letters of credit as collateral		17,000	18,100
Unbilled contracts receivable		48,300	46,100
Equity compensation		5,400	3,400	3,600
Advertising costs		6,200	7,900	$ 6,700
Cumulative impact of currency fluctuations		$ 1,300	$ 1,300
Lease-Related Exit Costs
Significant Accounting Policies [Line Items]
ASC 842 lease reclassification	$ 300
Revenue Benchmark | Services
Significant Accounting Policies [Line Items]
Concentration risk percentage		5.00%	5.00%	5.00%
Claims-Based Liability Insurance
Significant Accounting Policies [Line Items]
Self insured retention per claim		$ 500
Claims-Based Liability Insurance | MDA Holdings Inc
Significant Accounting Policies [Line Items]
Letter of credit for malpractice claims		$ 1,500	$ 1,800
Minimum
Significant Accounting Policies [Line Items]
Threshold period, past due for payment of services provided		30 days
Estimated useful life of assets		3 years
Short term leases period		3 months
Intangible assets- useful life		3 years
Maximum
Significant Accounting Policies [Line Items]
Threshold period, past due for payment of services provided		60 days
Estimated useful life of assets		10 years
Short term leases period		6 months
Intangible assets- useful life		16 years