Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Aug. 06, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	Green Bancorp, Inc.
Trading Symbol	gnbc
Entity Central Index Key	0001606363
Document Type	10-Q
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Current Fiscal Year End Date	--12-31
Document Period End Date	Jun. 30, 2018
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2018
Entity Common Stock, Shares Outstanding		37,308,313