Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Revenue	$ 98,248	$ 79,133	$ 264,803	$ 235,876
Costs and expenses:
Instructional costs and services	42,544	31,084	105,257	91,058
Selling and promotional	23,458	18,523	60,350	53,765
General and administrative	26,598	22,574	75,579	65,314
Loss on disposals of long-lived assets	0	418	182	742
Depreciation and amortization	4,386	3,226	9,561	9,955
Total costs and expenses	96,986	75,825	250,929	220,834
Income from operations before interest and income taxes	1,262	3,308	13,874	15,042
Interest (expense) income	(1,305)	121	(1,167)	1,002
(Loss) income before income taxes	(43)	3,429	12,707	16,044
Income tax expense	224	785	3,509	4,291
Equity investment loss	0	(2)	(827)	(2)
Net (loss) income	$ (267)	$ 2,642	$ 8,371	$ 11,751
Net (loss) income per common share:
Basic (in dollars per share)	$ (0.01)	$ 0.18	$ 0.47	$ 0.79
Diluted (in dollars per share)	$ (0.01)	$ 0.18	$ 0.46	$ 0.78
Weighted average number of common shares:
Basic (in shares)	18,700	14,797	17,874	14,870
Diluted (in shares)	18,855	15,011	18,048	15,021