Loans Receivable, net - Aging of Loans Receivable (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings between 29 and 59 days delinquent	$ 1.0
Troubled debt restructurings over 89 days delinquent		2.3
Commercial Mortgage Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings current	$ 5.8	$ 7.6