CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 420,899	$ 456,727
Restricted cash	1,221	1,089
Short-term investments	109,972	108,919
Accounts receivable, net	123,794	163,516
Prepaid expenses and other current assets	16,887	23,195
Total current assets	672,773	753,446
Property and equipment, net	45,300	50,154
Right-of-use assets	81,543	85,538
Deposits and other assets	14,596	8,024
Deferred tax assets, net	18,834	19,409
Total assets	833,046	916,571
Current liabilities:
Accounts payable, accrued expenses, and operating lease liabilities	31,468	33,919
Accrued compensation and employee benefits	40,806	48,792
Deferred revenue and advance payments	167,643	187,107
Total current liabilities	239,917	269,818
Deferred revenue and advance payments	5,910	4,344
Operating lease liabilities	98,283	103,424
Other long-term liabilities	30,452	30,400
Deferred tax liabilities	24	26
Total liabilities	374,586	408,012
Commitments and Contingencies
Stockholders’ Equity
Preferred stock undesignated, $0.001 par value; 5,000 shares authorized; no shares issued or outstanding	0	0
Additional paid-in capital	600,851	593,583
Treasury stock, at cost; 8,252 shares and 7,807 shares, respectively	(720,755)	(658,880)
Accumulated other comprehensive loss	(9,187)	(9,651)
Retained earnings	587,533	583,489
Total stockholders’ equity	458,460	508,559
Total liabilities and stockholders’ equity	833,046	916,571
Class A
Stockholders’ Equity
Common stock	16	16
Total stockholders’ equity	16	16
Class B Convertible
Stockholders’ Equity
Common stock	2	2
Total stockholders’ equity	$ 2	$ 2