Agreement With Russian Standard (Detail) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended
	May 04, 2012
Senior Notes Due 2013 [Member]
Long-term Purchase Commitment [Line Items]
Common stock purchase price per share	$ 5.25
Roust Trading Limited [Member]
Long-term Purchase Commitment [Line Items]
Common stock issued under purchase agreement, shares	5,714,286
Common stock purchase value under purchase agreement	$ 30
Common stock purchase price under purchase agreement	$ 5.25
Roust Trading Limited [Member] | Senior Notes Due 2013 [Member]
Long-term Purchase Commitment [Line Items]
Common stock issued under purchase agreement, shares	13,300,000
Senior notes purchased by affiliates	70
Senior notes purchased by affiliates due date	March 18, 2013
Interest rate percentage on issued debt	3.00%
Roust Trading Limited [Member] | Senior Rollover Notes Due 2013 [Member]
Long-term Purchase Commitment [Line Items]
Interest rate percentage on issued debt	6.00%
Debt instrument issuance amount	102.6
Debt instrument maturity date	Jul. 31, 2016
Roust Trading Limited [Member] | Senior Backstop Notes [Member]
Long-term Purchase Commitment [Line Items]
Interest rate percentage on issued debt	6.00%
Debt instrument issuance amount	$ 107.5
Debt instrument maturity date	Jul. 31, 2016