Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current Assets:
Cash and cash equivalents	$ 970,561	$ 1,247,652
Short-term investments	86,149	26,337
Accounts receivable, less allowance for doubtful accounts of $7,550 at June 30, 2014 and $8,695 at December 31, 2013	1,150,531	1,073,500
Deferred Federal and state income taxes	19,148	18,396
Other	84,081	49,384
Total current assets	2,310,470	2,415,269
Property and equipment, less accumulated depreciation and amortization of $366,800 at June 30, 2014 and $348,282 at December 31, 2013	556,228	563,064
Goodwill	7,927	7,927
Other assets, net	55,315	28,552
Total assets	2,929,940	3,014,812
Current Liabilities:
Accounts payable	717,141	648,156
Accrued expenses, primarily salaries and related costs	220,753	200,301
Federal, state and foreign income taxes	24,337	21,743
Total current liabilities	962,231	870,200
Deferred Federal and state income taxes	70,572	58,281
Commitments and contingencies
Shareholders' Equity:
Preferred stock, none issued	0	0
Common stock, par value $0.01 per share. Issued and outstanding 195,036,823 shares at June 30, 2014 and 202,553,220 shares at December 31, 2013	1,951	2,025
Additional paid-in capital	2,701	1,647
Retained earnings	1,893,771	2,087,376
Accumulated other comprehensive loss	(3,609)	(6,265)
Total shareholders’ equity	1,894,814	2,084,783
Noncontrolling interest	2,323	1,548
Total equity	1,897,137	2,086,331
Total liabilities and equity	$ 2,929,940	$ 3,014,812