Leucadia Merger and Related Transactions - Summary Computation of Purchase Price and Fair Values Assigned to Assets and Liabilities (Parenthetical) (Detail) (USD $)	3 Months Ended
	Feb. 28, 2013
Leucadia [Member]
Business Acquisition [Line Items]
Convertible Cumulative Preferred Stock, dividend rate	3.25%
Closing price common stock	$ 21.72
3.25% Cumulative Convertible Preferred Shares [Member]
Business Acquisition [Line Items]
Convertible Cumulative Preferred Stock, dividend rate	3.25%
3.25% Cumulative Convertible Preferred Shares [Member] | Leucadia [Member]
Business Acquisition [Line Items]
Convertible Cumulative Preferred Stock, dividend rate	3.25%
Series A-1 Convertible Cumulative Preferred Stock [Member]
Business Acquisition [Line Items]
Convertible Cumulative Preferred Stock, dividend rate	3.25%