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.

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- Definition

Percentage of Voting Interest

+ References

No definition available.

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- Definition

PercentofCentreLivingOperationsConsolidated

+ 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

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-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

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

+ 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 210.5-02.31)

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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 27

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 20

-Article 7

+ Details

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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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 $)	3 Months Ended		10 Months Ended	0 Months Ended
Related Party Transactions (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Oct. 27, 2014	Oct. 27, 2014	Dec. 31, 2014	Oct. 28, 2015
Related Party Transaction [Line Items]
Management fees expense – related party	$ 0grbk_ManagementFeeExpenseRelatedParty	$ 380,000grbk_ManagementFeeExpenseRelatedParty
Interest incurred	3,800,000	304,000
Ownership percentage by parent	50.00%
Ownership percentage by noncontrolling owners	50.00%
Net income	11,654,000us-gaap_MinorityInterest				9,739,000us-gaap_MinorityInterest
Executive
Related Party Transaction [Line Items]
Management fee percentage			0.375%
Management fees expense – related party	0	400,000
CentreLiving [Member]
Related Party Transaction [Line Items]
Percentage of voting interest	51.00%
Ownership percentage by parent	50.00%
Ownership percentage by noncontrolling owners	50.00%
PercentofCentreLivingOperationsConsolidated	100.00%
Net income	200,000
Texas Headquarters \| Selling, General and Administrative Expenses \| Family Members of CEO
Related Party Transaction [Line Items]
Rent expense	0	8,149
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	153,400,000
Interest incurred	$ 3,400,000
Reverse Recapitalization \| Scenario, Forecast \| Term Loan Facility \| Secured Debt \| Greenlight Capital, Inc
Related Party Transaction [Line Items]
Stated interest rate						10.00%