Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 187,509	$ 419,693
Marketable securities	7,557	34,874
Tuition receivable, net	50,169	51,523
Income taxes receivable	1,429	0
Other current assets	39,458	18,004
Total current assets	286,122	524,094
Property and equipment, net	158,854	117,029
Right-of-use lease assets	120,687	84,778
Marketable securities, non-current	30,270	36,633
Intangible assets, net	326,420	273,011
Goodwill	1,318,526	732,075
Other assets	54,928	21,788
Total assets	2,295,807	1,789,408
Current liabilities:
Accounts payable and accrued expenses	104,742	90,828
Income taxes payable	0	1,352
Contract liabilities	60,501	39,284
Lease liabilities	34,809	25,284
Total current liabilities	200,052	156,748
Long-term debt	141,823	0
Deferred income tax liabilities	53,407	47,942
Lease liabilities, non-current	106,151	80,557
Other long-term liabilities	46,055	41,451
Total liabilities	547,488	326,698
Commitments and contingencies
Stockholders’ equity:
Common stock, par value $0.01; 32,000,000 shares authorized; 21,964,809 and 24,418,939 shares issued and outstanding at December 31, 2019 and 2020, respectively	244	220
Additional paid-in capital	1,519,549	1,309,438
Accumulated other comprehensive income	48,880	233
Retained earnings	179,646	152,819
Total stockholders’ equity	1,748,319	1,462,710
Total liabilities and stockholders’ equity	$ 2,295,807	$ 1,789,408