CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 136,316	$ 94,622
Short term investments	415,499	326,653
Accounts receivable, net of allowance for doubtful accounts of $ 1,996 and $ 2,168 at June 30, 2013 and December 31, 2012, respectively	95,604	86,004
Revenue earned in excess of billings	27,423	11,875
Deferred income taxes and other current assets	51,884	51,736
Total current assets	726,726	570,890
Property and equipment	195,488	204,151
Less accumulated depreciation and amortization	84,111	85,033
Property and equipment, net	111,377	119,118
Goodwill	906	906
Non current term deposits with banks	2,663	14
Deferred income taxes and other non current assets	36,925	34,908
TOTAL ASSETS	878,597	725,836
Current liabilities:
Accounts payable	11,980	11,306
Accrued payroll and related costs	43,085	49,889
Income taxes payable	19,700	8,873
Accrued liabilities	31,190	23,644
Deferred revenue	2,838	4,694
Loans and borrowings	0	50,029
Total current liabilities	108,793	148,435
Other non current liabilities	12,035	11,731
Non current loans and borrowings	148,757	0
TOTAL LIABILITIES	269,585	160,166
SHAREHOLDERS' EQUITY
Total shareholders' equity	609,012	565,670
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 878,597	$ 725,836