Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 122,853	$ 79,611
Marketable securities	437	354
Trade accounts receivable, net of allowance for doubtful accounts of $7,608 and $6,728, respectively	436,452	372,159
Inventories	725,107	715,383
Deferred income tax assets	14,593	14,420
Other current assets	105,876	97,361
Prepaid income taxes	0	7,368
Total current assets	1,405,318	1,286,656
Property and equipment, less accumulated depreciation	575,571	516,427
Other assets, net	12,554	12,749
Total assets	1,993,443	1,815,832
Current liabilities:
Accounts payable	89,753	78,019
Accrued expenses	139,290	126,155
Income taxes payable	7,097	0
Total current liabilities	236,140	204,174
Deferred income tax liabilities	51,251	51,298
Stockholders' equity:
Preferred stock, 5,000,000 shares authorized	0	0
Common stock, 400,000,000 shares authorized, 296,860,119 and 296,564,382 shares issued and outstanding, respectively	2,969	2,966
Additional paid-in capital	73,344	61,436
Retained earnings	1,618,658	1,477,601
Accumulated other comprehensive income	11,081	18,357
Total stockholders' equity	1,706,052	1,560,360
Total liabilities and stockholders' equity	$ 1,993,443	$ 1,815,832