CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current assets
Cash and equivalents	$ 390,761	$ 186,513
Investment in short-term commercial paper	84,830
Accounts receivable, net of related allowances of $18,303 and $19,936 as of December 31, 2011 and 2010, respectively	679,898	584,068
Accounts receivable-related parties	42,893	38,121
Inventories	1,199,584	1,114,063
Deferred income taxes	25,341	20,684
Income taxes receivable	16,722	37,311
Other current assets	15,229	19,243
Total current assets	2,455,258	2,000,003
Property, plant and equipment, net	2,193,745	2,213,333
Restricted cash	26,528	23,132
Intangible assets, net of accumulated amortization of $181,227 and $142,880 as of December 31, 2011 and 2010, respectively	450,893	489,240
Goodwill	745,066	751,675
Other assets	107,736	112,551
Total assets	5,979,226	5,589,934
Current liabilities
Accounts payable	414,240	335,031
Accounts payable-related parties	6,584	13,570
Income taxes payable	10,880	5,227
Accrued payroll and benefits	68,752	62,051
Accrued profit sharing	38,671	23,524
Accrued interest	36,265	35,416
Accrued expenses	80,947	77,574
Current maturities of long-term debt	444,078	8,924
Total current liabilities	1,100,417	561,317
Long-term debt
Other long-term debt	37,272	40,397
Total long-term debt	1,936,022	2,377,897
Deferred income taxes	489,915	457,432
Other liabilities	82,278	62,159
Commitments and contingencies
Redeemable noncontrolling interests	70,694	54,294
Equity
Common stock voting, $.0025 par value; 900,000,000 shares authorized; 255,052,811 and 254,002,799 shares issued; and 218,873,720 and 217,574,826 shares outstanding, as of December 31, 2011 and 2010, respectively	636	633
Treasury stock, at cost; 36,179,091 and 36,427,973 shares, as of December 31, 2011, and 2010, respectively	(722,653)	(727,624)
Additional paid-in capital	1,026,157	998,728
Retained earnings	2,011,801	1,821,133
Total Steel Dynamics, Inc. equity	2,315,941	2,092,870
Noncontrolling interests	(16,041)	(16,035)
Total equity	2,299,900	2,076,835
Total liabilities and equity	5,979,226	5,589,934
7 3/8% senior notes, due 2012
Long-term debt
Senior notes	261,250	700,000
5.125% convertible senior notes, due 2014
Long-term debt
Convertible senior notes	287,500	287,500
6 3/4% senior notes, due 2015
Long-term debt
Senior notes	500,000	500,000
7 3/4% senior notes, due 2016
Long-term debt
Senior notes	500,000	500,000
7 5/8% senior notes, due 2020
Long-term debt
Senior notes	$ 350,000	$ 350,000