Net Revenue and Gross Profit By Product (Detail) (USD $)	3 Months Ended												12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule Of Entity Wide Revenue And Gross Profit By Major Products [Line Items]
Net revenue from unaffiliated customers	$ 254,879,358	$ 238,793,030	$ 191,007,886	$ 169,086,267	$ 177,579,159	$ 155,570,657	$ 167,012,527	$ 136,931,096	$ 135,471,182	$ 96,337,451	$ 75,502,350	$ 63,220,702	$ 853,766,541	$ 637,093,439	$ 370,531,685
Gross profit	24,945,946	25,256,402	20,711,034	18,634,992	19,701,206	19,456,930	19,647,463	16,908,073	20,658,741	15,121,824	14,500,306	11,821,284	89,548,374	75,713,672	62,102,155
Copper and CCA wire
Schedule Of Entity Wide Revenue And Gross Profit By Major Products [Line Items]
Net revenue from unaffiliated customers													393,782,161	335,574,034	243,132,742
Gross profit													47,885,410	49,722,321	50,934,170
Copper anode
Schedule Of Entity Wide Revenue And Gross Profit By Major Products [Line Items]
Net revenue from unaffiliated customers													381,114,304	287,269,353	97,613,692
Gross profit													37,667,562	25,224,807	8,506,764
Refined copper rod
Schedule Of Entity Wide Revenue And Gross Profit By Major Products [Line Items]
Net revenue from unaffiliated customers													78,870,076	14,250,052	29,785,251
Gross profit													$ 3,995,402	$ 766,544	$ 2,661,221