Business Combinations - Aggregated Consideration And Preliminary Purchase Price Allocation (Details) - Series of Individually Immaterial Business Acquisitions - USD ($) shares in Thousands, $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Business Acquisition, Contingent Consideration [Line Items]
Common Stock Issued (in shares)	122	33
Common Stock Value	$ 4,060	$ 885
Cash Paid	43,104	9,443
Other Payable	0	59
Recorded Contingent Consideration	20,124	4,670
Total Recorded Purchase Price	67,288	15,057
Identifiable Intangible Assets Acquired	22,393	3,629
Other Assets Acquired, net	5,878	270
Goodwill	39,017	11,158
Total Net Assets Acquired	67,288	15,057
Maximum Potential Contingent Consideration	$ 21,115	$ 6,202