Debt (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 235,807	$ 220,212
Amount outstanding	102,240	104,533
Amount of collateral	$ 160,339	$ 164,610
Interest rate	3.77%	3.91%
Master Repurchase Agreement \| March 30, 2016
Debt Instrument [Line Items]
Maturity Date		Mar. 30, 2016
Origination date		Sep. 30, 2015
Maximum borrowing capacity		$ 10,838
Amount outstanding		10,838
Amount of collateral		$ 15,483
Interest rate		2.53%
Master Repurchase Agreement \| June 23, 2016
Debt Instrument [Line Items]
Maturity Date		Jun. 23, 2016
Origination date		Dec. 23, 2015
Maximum borrowing capacity		$ 9,374
Amount outstanding		9,374
Amount of collateral		$ 13,391
Interest rate		2.91%
Master Repurchase Agreement \| September 09, 2016
Debt Instrument [Line Items]
Maturity Date	Sep. 09, 2016
Origination date	Mar. 09, 2016
Maximum borrowing capacity	$ 15,730
Amount outstanding	15,730
Amount of collateral	$ 22,470
Interest rate	3.00%
Master Repurchase Agreement \| September 30, 2016
Debt Instrument [Line Items]
Maturity Date	Sep. 30, 2016
Origination date	Mar. 30, 2016
Maximum borrowing capacity	$ 10,658
Amount outstanding	10,658
Amount of collateral	$ 15,226
Interest rate	3.01%
Master Repurchase Agreement \| November 22, 2016
Debt Instrument [Line Items]
Maturity Date	Nov. 22, 2016	Nov. 22, 2016
Origination date	Nov. 24, 2015	Nov. 24, 2015
Maximum borrowing capacity	$ 200,000	$ 200,000
Amount outstanding	66,433	84,321
Amount of collateral	$ 109,252	$ 135,736
Interest rate	4.19%	4.17%
Master Repurchase Agreement \| December 23, 2016
Debt Instrument [Line Items]
Maturity Date	Dec. 23, 2016
Origination date	Jun. 23, 2016
Maximum borrowing capacity	$ 9,419
Amount outstanding	9,419
Amount of collateral	$ 13,391
Interest rate	2.91%

Represents amount related to maximum borrowing capacity of debt instrument.

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Amount of assets pledged to secure a debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Period Type:	instant

- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

+ References

+ Details

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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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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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- Details

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