Income Taxes - Tax Rate Reconciliation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Federal income tax statutory rate (as a percent)	35.00%	35.00%	34.00%
Reconciliation of provision for income taxes
Taxes calculated at statutory rate	$ 8,087	$ 6,831	$ 4,391
Increase (decrease) resulting from:
State tax expense, net of federal effect	209	174	119
Non-deductible expenses	35	65	58
Incentive stock compensation expense	34	5	9
Bargain purchase gain			(197)
Change in applicable statutory rate		(211)
Other, net		42
Income Tax Expense (Benefit), Total	8,365us-gaap_IncomeTaxExpenseBenefit	6,906us-gaap_IncomeTaxExpenseBenefit	4,380us-gaap_IncomeTaxExpenseBenefit
Green Bancorp, Inc.
Increase (decrease) resulting from:
Income Tax Expense (Benefit), Total	$ (654)	$ (346)	$ (280)

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