Payables and Accrued Liabilities - Payables and Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Payables And Accruals [Abstract]
Collateral payable on derivative instruments	$ 124,759
Servicing rights purchases payable and related advances	67,580	21,011
Payables to insurance carriers	67,548	51,377
Derivative instruments	58,606	1,102
Employee related liabilities	58,081	37,124
Curtailment liability	44,800
Originations liability	32,727	675
Servicing transfer payables	28,926	11,275
Income tax payable	21,280
Uncertain tax positions	22,612	26,301
Acquisition related escrow funds payable to sellers	18,870	14,000
Accrued interest payable	14,719	10,764
Contingent earn-out payments	10,900	6,100
Mandatory repurchase obligation	8,867	9,999
Professional fees liability related to certain securitizations	7,350	8,147
Other	113,724	62,735
Total payables and accrued liabilities	$ 701,349	$ 260,610