Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 28, 2018	Dec. 29, 2017
Current assets:
Cash and cash equivalents	$ 120,977	$ 124,794
Short-term investments	81,373	71,604
Accounts receivable, net of allowance for contract losses and doubtful accounts of $3,912 and $3,526 at September 28, 2018 and December 29, 2017, respectively	122,911	110,100
Prepaid expenses and other assets	11,243	9,011
Total current assets	336,504	315,509
Property, equipment and leasehold improvements, net	43,969	35,014
Goodwill	8,607	8,607
Deferred income taxes	32,966	30,437
Deferred compensation plan assets	57,432	48,676
Other assets	1,415	1,346
Total assets	480,893	439,589
Current liabilities:
Accounts payable and accrued liabilities	13,221	14,741
Accrued payroll and employee benefits	66,060	70,064
Deferred revenues	8,864	8,302
Total current liabilities	88,145	93,107
Other liabilities	2,911	3,326
Deferred compensation	57,998	52,776
Deferred rent	1,205	1,292
Total liabilities	150,259	150,501
Stockholders' equity:
Common stock, $0.001 par value; 120,000 shares authorized; 65,707 shares issued at September 28, 2018 and December 29, 2017	66	66
Additional paid-in capital	225,454	210,230
Accumulated other comprehensive income (loss)
Investment securities, available-for-sale	(288)	(236)
Foreign currency translation adjustments	(2,726)	(1,793)
Accumulated other comprehensive income (loss)	(3,014)	(2,029)
Retained earnings	332,907	303,990
Treasury stock, at cost; 13,655 and 14,169 shares held at September 28, 2018 and December 29, 2017, respectively	(224,779)	(223,169)
Total stockholders' equity	330,634	289,088
Total liabilities and stockholders' equity	$ 480,893	$ 439,589