Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Cash flows from operating activities
Net income	$ 71,273	$ 65,202
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for deferred income taxes	7,894	6,269
Depreciation and amortization	10,607	4,385
Deferred financing costs and derivative and accretion expense	1,171	983
Stock-based and deferred compensation	4,792	9,471
Change in fair value of contingent consideration obligations	(3,500)	2,500
Unrealized depreciation (appreciation) on investments	452	(2,720)
Noncash lease expense	94
Loss on equity method investment	57	92
Loss on debt extinguishment	1,555	2,781
Changes in operating assets and liabilities:
Receivables	4,210	(6,730)
Prepaid expenses	(1,260)	(695)
Other assets	(80)
Accounts payable and accrued expenses	(8,819)	13,573
Accrued compensation and benefits	(13,487)	(14,987)
Other liabilities	(146)	(490)
Net cash provided by operating activities	74,813	79,634
Cash flows from investing activities
Purchases of property and equipment	(1,176)	(393)
Purchases of investments	(2,365)	(2,626)
Sales of investments	1,249	1,909
Purchase of equity method investment	(1,500)
Acquisition of business and assets, net of cash acquired	(327)	(30)
Net cash used in investing activities	(4,119)	(1,140)
Cash flows from financing activities
Issuance of common stock	1,302	834
Repurchase of common stock	(10,193)	(7,661)
Payments of taxes related to net share settlement of equity awards	(5,373)	(7,614)
Repayment of long-term senior debt	(70,000)	(50,000)
Payment of dividends	(17,381)	(6,393)
Net cash used in financing activities	(101,645)	(70,834)
Effect of changes of foreign exchange rate on cash and cash equivalents	(32)	(18)
Net increase in cash and cash equivalents	(30,983)	7,642
Cash and cash equivalents, beginning of period	69,533	22,744	$ 22,744
Cash and cash equivalents, end of period	38,550	30,386	$ 69,533
Supplemental cash flow information
Cash paid for interest	7,074	8,096
Cash paid for income taxes	1,012	$ 831
Noncash items
Operating lease right-of-use assets obtained in exchange for new operating lease liabilities	$ 2,991