LOANS AND ASSET QUALITY (Details 1) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Troubled debt restructured loans	$ 307	$ 312
Non-accrual and 90 days or more and still accruing loans to gross loans	1.41%	1.43%
Allowance for credit losses to non-accrual and 90 days or more and still accruing loans	68.35%	65.59%

Represents Allowance for credit losses to non-accrual and 90 days or more and still accruing loans.

No definition available.

Name:	glbz_AllowanceForCreditLossesToNonAccrualAnd90DaysOrMoreAndStillAccruingLoans
Namespace Prefix:	glbz_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant