Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 94,622	$ 104,628
Short-term investments	326,653	215,798
Accounts receivable, net of allowance for doubtful accounts of $2,168 and $2,407 at December 31, 2012 and 2011, respectively	86,004	88,573
Revenue earned in excess of billings	11,875	5,131
Deferred income taxes and other current assets	51,736	46,353
Total current assets	570,890	460,483
Property and equipment	204,151	179,576
Less accumulated depreciation and amortization	85,033	73,574
Property and equipment, net	119,118	106,002
Goodwill	906	906
Non current term deposits with banks	14	130
Deferred income taxes and other non current assets	34,908	29,727
Total assets	725,836	597,248
Current liabilities:
Accounts payable	11,306	12,299
Accrued payroll and related costs	49,889	45,949
Income taxes payable	8,873	3,080
Accrued liabilities	23,644	20,309
Deferred revenue	4,694	9,692
Loans and borrowings	50,029
Dividends payable		2,733
Total current liabilities	148,435	94,062
Other non current liabilities	11,731	9,997
TOTAL LIABILITIES	160,166	104,059
SHAREHOLDERS' EQUITY
Common Stock, no par value per share, 100,000,000 shares authorized; 41,659,778 and 41,571,338 shares issued and outstanding at December 31, 2012 and 2011, respectively	1	1
Restricted stock, 260,859 and 243,440 shares issued and outstanding at December 31, 2012 and 2011, respectively	18,062	13,692
Additional paid-in capital	67,422	67,422
Accumulated other comprehensive (loss)	(86,133)	(72,434)
Retained earnings	566,318	484,508
Total shareholders' equity	565,670	493,189
Total liabilities and shareholders' equity	$ 725,836	$ 597,248