Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating Activities
Net income	$ 13,593	$ 8,974
Adjustments to reconcile net income to net cash provided by (used in) operations:
Depreciation	1,460	1,288
Amortization	7,052	3,922
Deferred income taxes	455	1,608
Non-cash stock compensation and retirement savings plan contributions	5,113	4,607
Amortization of debt discount and issuance costs	2,528	1,201
Adjustment to fair value of contingent consideration for purchase of businesses	514	(335)
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable	(5,653)	7,656
Other assets	(3,065)	479
Accounts payable	(7,844)	(7,583)
Other liabilities	(12,992)	(26,201)
Net cash provided by (used in) operating activities	1,161	(4,384)
Investing Activities
Purchase of property and equipment	(1,480)	(1,513)
Capitalization of internally developed software costs	(348)	(497)
Purchase of businesses, net of cash acquired	0	(29,785)
Net cash used in investing activities	(1,828)	(31,795)
Financing Activities
Proceeds from the sale of stock through the Employee Stock Purchase Plan	105	40
Purchases of treasury stock	(4,908)	0
Remittance of taxes withheld as part of a net share settlement of restricted stock vesting	(5,234)	(4,835)
Net cash used in financing activities	(10,037)	(4,795)
Effect of exchange rate on cash and cash equivalents	(442)	(453)
Change in cash and cash equivalents	(11,146)	(41,427)
Cash and cash equivalents at beginning of period	83,204	70,728
Cash and cash equivalents at end of period	72,058	29,301
Supplemental Disclosures:
Cash paid for income taxes	1,218	397
Cash paid for interest	1,445	1,759
Non-Cash Investing Activity:
Stock issued for purchase of businesses	0	4,239
Liability incurred for purchase of property and equipment	$ 0	$ 307