CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 299,208	$ 366,853
Short-term investments	650,967	447,972
Trade receivables	505,551	542,990
Merchandise inventories	1,314,301	1,361,709
Deferred tax assets	68,062	59,400
Prepaid expenses	36,009	24,316
Total current assets	2,874,098	2,803,240
Long-term investments	4,155,087	3,805,283
Other noncurrent assets	188,559	171,179
Property, plant and equipment	8,737,469	8,621,316
Accumulated depreciation	(4,185,240)	(4,132,786)
Net property, plant and equipment	4,552,229	4,488,530
Assets, Total	11,769,973	11,268,232
Current liabilities:
Accounts payable	1,215,277	1,133,120
Accrued expenses:
Contribution to retirement plans	282,140	405,818
Self-insurance reserves	128,070	125,569
Salaries and wages	189,165	110,207
Other	314,552	221,713
Current portion of long-term debt	56,522	15,124
Federal and state income taxes		39,225
Total current liabilities	2,185,726	2,050,776
Deferred tax liabilities	300,537	316,802
Self-insurance reserves	224,342	219,660
Accrued postretirement benefit cost	103,849	103,595
Long-term debt	82,610	119,460
Other noncurrent liabilities	116,666	116,482
Total liabilities	3,013,730	2,926,775
Common stock related to Employee Stock Ownership Plan (ESOP)	2,334,234	2,137,217
Stockholders' equity:
Common stock of $1 par value. Authorized 1,000,000 shares; issued and outstanding 790,157 shares in 2012 and 779,675 shares in 2011	790,157	779,675
Additional paid-in capital	1,584,900	1,354,881
Retained earnings	6,457,609	6,131,193
Treasury stock at cost, 7,033 shares in 2012	(158,892)
Accumulated other comprehensive earnings	36,763	30,261
Common stock related to ESOP	(2,334,234)	(2,137,217)
Total stockholders' equity	6,376,303	6,158,793
Noncontrolling interests	45,706	45,447
Total equity	8,756,243	8,341,457
Liabilities and stockholders' equity, total	$ 11,769,973	$ 11,268,232