Series C Convertible Preferred Stock Installments (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Class Of Stock [Line Items]
Dividend, installment payments	$ 696	$ 3,431
Principal, installment payments	8,446	31,120
Total, installment payments	9,142	34,551
Dividend, cash		2,400
Principal, cash		23,340
Total		25,740
Dividend, stock		1,031
Principal, stock		7,780	7,780
Total, stock		$ 8,811
Dividend, stock (shares)		80,169
Principal, stock (shares)		600,309
Total, stock (shares)		680,478