Related Party Transactions (Detail) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Receivable for advisory and service fees, from affiliates	$ 6,498,000		$ 6,839,000	[1]
Management Agreement
Basis for management fee	Amount equal to 1/12th of 1.05% of stockholders' equity,
Initial term of management agreement expiration date	Dec. 31, 2014
Chimera
Investments with affiliate, available-for-sale equity securities - shares	45.0		45.0
Investments with affiliate, available-for-sale equity securities - fair value	137,600,000		139,400,000
Investments with affiliate, available-for-sale equity securities - unrealized gains	1,200,000		600,000
Automatic Renewal | Management Agreement
Renewal term	1 year
Chimera and CreXus
Advisory fees from affiliate	6,100,000	9,300,000
Receivable for advisory and service fees, from affiliates	$ 6,500,000		$ 6,800,000

[1] Derived from the audited consolidated financial statements at December 31, 2013.