Intangible Asset Rollforward (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Finite-Lived and Indefinite-lived Intangible Assets [Roll Forward]
At period start	$ 3,455	$ 786
At period start	3,455
Additions		2,669
Additions	482,445
Impairment	(6,000)
At period end		3,455	786
At period end	479,900	3,455
At period start	383	147
Amortization	28,579	236	100
At period end	28,962	383	147
Net book value	450,938	3,072
Trade names
Finite-Lived and Indefinite-lived Intangible Assets [Roll Forward]
At period end	15,586
Net book value	14,434
Trade names
Finite-Lived and Indefinite-lived Intangible Assets [Roll Forward]
Additions	14,800
Customer relationships
Finite-Lived and Indefinite-lived Intangible Assets [Roll Forward]
At period start	2,669	0
Additions	342,105	2,669
Impairment	0
At period end	344,774	2,669
At period start	170	0
Amortization	13,925	170
At period end	14,095	170
Net book value	330,679	2,499
Rare earth quotas
Finite-Lived and Indefinite-lived Intangible Assets [Roll Forward]
At period start	0	0
Additions	78,300	0
Impairment	0
At period end	78,300	0
At period start	0	0
Amortization	4,035	0
At period end	4,035	0
Net book value	74,265	0
Patents
Finite-Lived and Indefinite-lived Intangible Assets [Roll Forward]
At period start	0	0
Additions	39,252	0
Impairment	(6,000)
At period end	33,252	0
At period start	0	0
Amortization	9,365	0
At period end	9,365	0
Net book value	23,887	0
Trade names
Finite-Lived and Indefinite-lived Intangible Assets [Roll Forward]
At period start	786	786
At period start	786
Additions		0
Impairment	0
At period end		786
At period end		786
At period start	213	147
Amortization	939	66
At period end	1,152	213
Net book value		573
Land use rights
Finite-Lived and Indefinite-lived Intangible Assets [Roll Forward]
At period start	0	0
Additions	3,568	0
Impairment	0
At period end	3,568	0
At period start	0	0
Amortization	66	0
At period end	66	0
Net book value	3,502	0
Other
Finite-Lived and Indefinite-lived Intangible Assets [Roll Forward]
At period start	0	0
Additions	4,420	0
Impairment	0
At period end	4,420	0
At period start	0	0
Amortization	249	0
At period end	249	0
Net book value	$ 4,171	$ 0