Management fee expense paid to related party.

No definition available.

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- Definition

Management fee percentage paid to related party.

+ References

No definition available.

+ Details

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- Definition

Percentage of Voting Interest

+ References

No definition available.

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- Definition

Secured Debt, Including Interest Payable

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Interest and fee income generated from loans secured by commercial properties. Examples of properties commonly securing commercial real estate loans may include office buildings, apartment buildings, shopping centers, industrial property, and hotels.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.1)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 1

-Article 9

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

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- Definition

The amount of interest capitalized to an operative builder's inventory during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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Related Party Transactions (Details) (USD $)	12 Months Ended			10 Months Ended	11 Months Ended	0 Months Ended
Related Party Transactions (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 27, 2014	Nov. 30, 2014	Oct. 27, 2014	Oct. 28, 2015
Related Party Transaction [Line Items]
Management fees expense – related party	$ 1,266,000grbk_ManagementFeeExpenseRelatedParty	$ 1,016,000grbk_ManagementFeeExpenseRelatedParty	$ 581,000grbk_ManagementFeeExpenseRelatedParty
Interest incurred	4,146,000	1,380,000	405,000
Executive
Related Party Transaction [Line Items]
Management fee percentage				0.375%
Management fees expense – related party		1,016,000	581,000	1,300,000
Selling, General and Administrative Expenses
Related Party Transaction [Line Items]
Rent expense	500,000	200,000	100,000
Interest and Fees Income \| Affiliates of Company
Related Party Transaction [Line Items]
Interest income	0	700,000	900,000
Texas Headquarters \| Selling, General and Administrative Expenses \| Family Members of CEO
Related Party Transaction [Line Items]
Rent expense		28,137	18,000		13,913
Reverse Recapitalization \| Term Loan Facility \| Secured Debt \| Greenlight Capital, Inc
Related Party Transaction [Line Items]
Percentage of voting interest				49.90%		49.90%
Debt instrument, term						5 years
Debt instrument, face amount				150,000,000		150,000,000
Stated interest rate				9.00%		9.00%
Accrued interest payable	152,400,000
Interest incurred	$ 2,400,000
Reverse Recapitalization \| Scenario, Forecast \| Term Loan Facility \| Secured Debt \| Greenlight Capital, Inc
Related Party Transaction [Line Items]
Stated interest rate							10.00%