Summary of Tax Losses Carried Forward (Detail)	12 Months Ended
	Dec. 31, 2012
Hungary
Operating Loss Carryforwards [Line Items]
Maximum number of years tax losses can be carried forward	Unrestricted period	[1]
Maximum | United States
Operating Loss Carryforwards [Line Items]
Maximum number of years tax losses can be carried forward	20 years
Maximum | Russia
Operating Loss Carryforwards [Line Items]
Maximum number of years tax losses can be carried forward	10 years
Maximum | Poland
Operating Loss Carryforwards [Line Items]
Maximum number of years tax losses can be carried forward	5 years

[1] In some circumstances the Tax Office's permission to carry the loss forward is required.