XML 45 R31.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Share-Based Compensation (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |
Schedule of Share-based Compensation, Activity | The following table summarizes the share-based compensation expense incurred by the Company (in thousands):
| Years Ended December 31,
| 2014 |  | 2013 |  | 2012
Stock options | $ | (40 | ) |  | $ | — |  |  | $ | — |
Summary of Stock Option Activity | A summary of stock option activity as of December 31, 2014, and the changes during the year ended December 31, 2014 is as follows:
| Number of Shares (in thousands) |  | Weighted Average Exercise Price per Share |  | Weighted Average Remaining Contractual Term (in years) |  | Aggregate Intrinsic Value (in thousands)
Options outstanding, January 1, 2014 | — |  |  | $ | — |  |  |  |  |
Granted | 500 |  |  | 7.49 |  |  |  |  |
Exercised | — |  |  | — |  |  |  |  |
Forfeited | — |  |  | — |  |  |  |  |
Options outstanding, December 31, 2014 | 500 |  |  | $ | 7.49 |  |  | 9.82 |  |  | $ | 357 |
Options exercisable, December 31, 2014 | — |  |  | $ | — |  |  | — |  |  | $ | — |
Summary of Unvested Stock Options Activity | A summary of our unvested stock options as of December 31, 2014, and the changes during the year ended December 31, 2014 is as follows (shares in thousands):
| Number of Shares (in thousands) |  | Weighted Average Per Share Grant Date Fair Value
Unvested, January 1, 2014 | — |  |  | $ | — |
Granted | 500 |  |  | $ | 2.88 |
Vested | — |  |  | $ | — |
Forfeited | — |  |  | $ | — |
Unvested, December 31, 2014 | 500 |  |  | $ | 2.88 |
Schedule of Stock Options, Valuation Assumptions | We utilized the Black-Scholes option pricing model for estimating the grant date fair value of stock options with the following assumptions:
| Risk-Free Interest Rate |  | Expected Term (in years) |  | Weighted Average Expected Stock Price Volatility |  | Expected Dividend Yield |  | Weighted Average Per Share Grant Date Fair Value
Fiscal year 2014 | 1.94 | % |  | 6.5 |  | 37.2 | % |  | — | % |  | $ | 2.88 |

X
- Definition Tabular disclosure represents the unvested stock options during the period. + References No definition available. + Details
Name: | grbk_ScheduleOfUnvestedStockOptionsTableTableTextBlock
Namespace Prefix: | grbk_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of share-based compensation plans that may be presented in a single table for outstanding, vested and expected to vest, and exercisable awards. The information that may be disclosed in this table may include, but is not limited to, number of shares, weighted average exercise price, weighted average remaining contractual life, and aggregate intrinsic value. + References No definition available. + Details
Name: | us-gaap_ScheduleOfShareBasedCompensationActivityTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration