Commitments and Contingencies (Details)	9 Months Ended
Sep. 30, 2016 USD ($) lease
Lease Commitments
Number of operating leases \| lease	2
Residential whole loans held at carrying value excluded, purchase transaction not occurred	$ 111,200,000
Residential whole loans held at fair value excluded, purchase transaction not occurred	92,800,000
Corporate headquarters
Lease Commitments
Irrevocable standby letter of credit provided to landlord	785,000
Corporate headquarters \| High end of range
Lease Commitments
Aggregate annual lease payments	2,500,000
Off-site back-up facility \| High end of range
Lease Commitments
Aggregate annual lease payments	30,000
Loan Purchase Commitments \| Residential whole loans
Lease Commitments
Commitment for residential whole loan purchase	$ 204,000,000

Represents the number of operating leases.

No definition available.

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- Definition

Residential Whole Loans Held at Carrying Value Excluded, Purchase Transaction Not Occurred

+ References

No definition available.

+ Details

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- Definition

Residential Whole Loans Held at Fair Value Excluded, Purchase Transaction Not Occurred

+ References

No definition available.

+ Details

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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