Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Current Assets:
Cash and cash equivalents	$ 1,286,109	$ 1,260,842
Short-term investments	89,902	139
Accounts receivable, less allowance for doubtful accounts of $8,933 at June 30, 2013 and $9,383 at December 31, 2012	1,018,337	1,031,376
Deferred Federal and state income taxes	11,999	12,102
Other	69,431	53,140
Total current assets	2,475,778	2,357,599
Property and equipment, less accumulated depreciation and amortization of $334,988 at June 30, 2013 and $325,595 at December 31, 2012	549,583	556,204
Goodwill	7,927	7,927
Other assets, net	30,377	32,395
Total assets	3,063,665	2,954,125
Current Liabilities:
Accounts payable	645,196	641,593
Accrued expenses, primarily salaries and related costs	196,789	178,995
Federal, state and foreign income taxes	18,228	21,970
Total current liabilities	860,213	842,558
Deferred Federal and state income taxes	81,510	78,997
Commitments and contingencies
Shareholders' Equity:
Preferred stock, none issued	0	0
Common stock, par value $.01 per share. Issued and outstanding 206,321,425 shares at June 30, 2013 and 206,392,013 shares at December 31, 2012	2,063	2,064
Additional paid-in capital	3,534	1,283
Retained earnings	2,129,349	2,018,618
Accumulated other comprehensive (loss) income	(15,105)	5,734
Total shareholders’ equity	2,119,841	2,027,699
Noncontrolling interest	2,101	4,871
Total equity	2,121,942	2,032,570
Total liabilities and equity	$ 3,063,665	$ 2,954,125