CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 379,694	$ 401,975
Restricted cash	833	737
Short-term investments	252,701	187,408
Accounts receivable, net	68,005	83,319
Prepaid expenses and other current assets	13,951	11,548
Total current assets	715,184	684,987
Property and equipment, net	54,490	57,436
Capitalized software development costs, net	5,498	8,497
Deposits and other assets	6,055	5,695
Deferred tax assets, net	15,871	11,704
Total assets	797,098	768,319
Current liabilities:
Accounts payable and accrued expenses	23,701	36,628
Accrued compensation and employee benefits	34,811	43,323
Deferred revenue and advance payments	123,082	105,535
Total current liabilities	181,594	185,486
Deferred revenue and advance payments	10,697	13,915
Other long-term liabilities	14,810	16,447
Deferred tax liabilities	310	294
Total liabilities	207,411	216,142
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	552,541	543,974
Treasury stock, at cost; 6,405 shares	(475,184)	(475,184)
Accumulated other comprehensive loss	(7,743)	(10,743)
Retained earnings	520,055	494,112
Total stockholders' equity	589,687	552,177
Total liabilities and stockholders' equity	797,098	768,319
Class A
Stockholders' Equity
Common stock	16	16
Class B Convertible
Stockholders' Equity
Common stock	$ 2	$ 2