Parent Company Only Financial Statements - Condensed Statements of Operations (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
INCOME-Interest income	$ 79,605	$ 68,459	$ 61,581
Total noninterest expense	52,433us-gaap_NoninterestExpense	39,965us-gaap_NoninterestExpense	35,742us-gaap_NoninterestExpense
INCOME BEFORE INCOME TAXES	23,107	19,516	12,915
BENEFIT FOR INCOME TAXESBENEFIT FOR INCOME TAXES	(8,365)us-gaap_IncomeTaxExpenseBenefit	(6,906)us-gaap_IncomeTaxExpenseBenefit	(4,380)us-gaap_IncomeTaxExpenseBenefit
NET INCOME	14,742us-gaap_NetIncomeLoss	12,610us-gaap_NetIncomeLoss	8,535us-gaap_NetIncomeLoss
Green Bancorp, Inc.
INCOME-Interest income	26	23	27
Total income	26	23	27
EXPENSE-General and administrative	1,894	1,012	851
Total noninterest expense	1,894	1,012	851
LOSS BEFORE EQUITY IN UNDISTRIBUTED EARNINGS OF SUBSIDIARY AND INCOME TAXES	(1,868)	(989)	(824)
EQUITY IN UNDISTRIBUTED EARNINGS OF SUBSIDIARY, Net of tax	(15,957)	(13,253)	(9,079)
INCOME BEFORE INCOME TAXES	14,089	12,264	8,255
BENEFIT FOR INCOME TAXESBENEFIT FOR INCOME TAXES	654	346	280
NET INCOME	$ 14,743	$ 12,610	$ 8,535

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