Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Current Assets:
Cash and cash equivalents	$ 1,412,915	$ 1,294,356
Short-term investments	16,277	472
Accounts receivable, less allowance for doubtful accounts of $9,805 at March 31, 2012 and $10,381 at December 31, 2011	934,866	934,752
Deferred Federal and state income taxes	9,754	10,415
Other	36,386	46,888
Total current assets	2,410,198	2,286,883
Property and equipment, less accumulated depreciation and amortization of $306,524 at March 31, 2012 and $296,481 at December 31, 2011	550,323	538,806
Goodwill and other intangibles, net	10,215	10,557
Other assets, net	30,487	30,581
Total assets	3,001,223	2,866,827
Current Liabilities:
Accounts payable	629,503	606,628
Accrued expenses, primarily salaries and related costs	170,535	169,445
Federal, state and foreign income taxes	28,219	20,072
Total current liabilities	828,257	796,145
Deferred Federal and state income taxes	70,932	60,613
Commitments and contingencies
Shareholders' Equity:
Preferred stock, none issued	0	0
Common stock, par value $.01 per share. Issued and outstanding 211,275,083 shares at March 31, 2012 and 212,003,662 shares at December 31, 2011	2,123	2,120
Additional paid-in capital	18,338	13,260
Retained earnings	2,067,929	1,991,222
Accumulated other comprehensive income (loss)	7,064	(2,964)
Total shareholders' equity	2,095,454	2,003,638
Noncontrolling interest	6,580	6,431
Total equity	2,102,034	2,010,069
Total liabilities and equity	$ 3,001,223	$ 2,866,827