Acquisitions and Dispositions - Additional Information (Detail) - USD ($) $ in Thousands		8 Months Ended	12 Months Ended
	May 06, 2019	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Accumulated Amortization through December 31, 2019			$ 37,357	$ 33,487	$ 33,807
Contingent liability from 1st Global acquisition		$ 11,052	11,052	0
Proceeds from sale of business, net of cash divested			7,467	0	$ 0
Gain on sale of investment			3,300	$ 2,100
1st Global
Business Acquisition [Line Items]
Cash	$ 12,389
Business combination purchase price	180,000
Accumulated Amortization through December 31, 2019			4,936
Contingent liability	10,000	11,052	11,052
Cash to be paid after the 1st Global Acquisition date		3,150
Tangible assets acquired including cash of $12,389	2,100
Gross amount of acquired receivables	$ 6,700
Acquisition related costs			6,500
Revenue from acquiree since acquisition date		114,800
Earnings of acquiree since acquisition date		$ 300
SimpleTax
Business Acquisition [Line Items]
Proceeds from sale of business, net of cash divested			$ 9,600