Mortgage-Backed Debt and Related Collateral - Summary of Collateral for Mortgage-Backed Debt (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Dec. 31, 2012
Financial Instruments Owned and Pledged as Collateral [Line Items]
Residential loans of securitization trusts, principal balance	$ 252,080,666	$ 217,961,136	$ 90,094,189
Receivables related to Non-Residual Trusts	36,181	43,545	53,975
Real estate owned, net	79,079	73,573	64,959
Restricted cash and cash equivalents	811,670	804,803	653,338
VIE Primary Beneficiary [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Receivables related to Non-Residual Trusts	36,181	43,545
Restricted cash and cash equivalents	71,125	59,080	59,233
Total mortgage-backed debt collateral		2,400,000
VIE Primary Beneficiary [Member] \| Mortgage-backed Debt [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Residential loans of securitization trusts, principal balance		2,248,467	2,458,678
Receivables related to Non-Residual Trusts		43,545	53,975
Real estate owned, net		42,298	43,115
Restricted cash and cash equivalents		58,081	58,253
Total mortgage-backed debt collateral		$ 2,392,391	$ 2,614,021

Fair value portion of amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties.

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Amount of assets pledged to secure a debt instrument.

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This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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