FAIR VALUE - Estimated fair values of the Company's financial instruments (Details 1) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financial assets - Carrying Amount
Cash and due from banks	$ 6,247us-gaap_CashAndDueFromBanks	$ 7,101us-gaap_CashAndDueFromBanks
Interest-bearing deposits	6,136us-gaap_InterestBearingDepositsInBanks	2,155us-gaap_InterestBearingDepositsInBanks
Federal funds sold	5,058us-gaap_FederalFundsSold	4,024us-gaap_FederalFundsSold
Investment securities	97,316us-gaap_AvailableForSaleSecurities	87,993us-gaap_AvailableForSaleSecurities
Investments in restricted stock	1,203	1,328
Ground rents	169us-gaap_GroundLeasesNet	169us-gaap_GroundLeasesNet
Loans, net	268,233	273,986
Accrued interest receivable	1,099us-gaap_InterestReceivable	1,274us-gaap_InterestReceivable
Financial liabilities - Carrying Amount
Deposits	346,571us-gaap_Deposits	338,877us-gaap_Deposits
Long-term borrowings	20,000us-gaap_LongTermDebt	20,000us-gaap_LongTermDebt
Dividends payable	276	276
Accrued interest payable	42	40
Off-balance sheet commitments	25,786glbz_OffBalanceSheetFirmCommitments	21,430glbz_OffBalanceSheetFirmCommitments
Financial assets - Fair Value
Cash and due from banks	6,247glbz_CashAndDueFromBanksFairValue	7,101glbz_CashAndDueFromBanksFairValue
Interest-bearing deposits	6,136glbz_InterestBearingDepositFairValue	2,155glbz_InterestBearingDepositFairValue
Federal funds sold	5,058glbz_FederalFundsSoldFairValue	4,024glbz_FederalFundsSoldFairValue
Investment securities	97,316us-gaap_AvailableForSaleSecurities	87,993us-gaap_AvailableForSaleSecurities
Investments in restricted stock	1,203	1,328
Ground rents	169glbz_GroundRentsFairValue	169glbz_GroundRentsFairValue
Loans, net	263,097	268,536
Accrued interest receivable	1,099glbz_AccruedInterestReceivableFairValue	1,274glbz_AccruedInterestReceivableFairValue
Financial liabilities - Fair Value
Deposits	319,332us-gaap_DepositsFairValueDisclosure	310,239us-gaap_DepositsFairValueDisclosure
Long-term borrowings	21,035us-gaap_LongTermDebtFairValue	20,951us-gaap_LongTermDebtFairValue
Dividends payable	276glbz_DividendsPayableFairValue	276glbz_DividendsPayableFairValue
Accrued interest payable	42glbz_AccruedInterestPayableFairValue	40glbz_AccruedInterestPayableFairValue
Off-balance sheet commitments	$ 25,786glbz_OffBalanceSheetFirmCommitments	$ 21,430glbz_OffBalanceSheetFirmCommitments

Accrued interest payable fair value

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- Definition

Accrued interest receivable fair value

+ References

No definition available.

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- Definition

Cash and due from banks fair value

+ References

No definition available.

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- Definition

Dividends payable fair value

+ References

No definition available.

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- Definition

Federal funds sold fair value

+ References

No definition available.

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- Definition

Ground rents fair value.

+ References

No definition available.

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- Definition

Interest bearing deposit fair value

+ References

No definition available.

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- Definition

Represents amount consisted of related to off balance sheet commitment.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

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-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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- Definition

For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.1)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1, 2, 3

-Article 9

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Balance Type:	debit
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- Definition

Amount of accrued but unpaid interest on deposit liabilities.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

+ Details

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Period Type:	instant

- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

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-Number 210

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-Subparagraph a

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-Number 210

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-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Balance Type:	credit
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- Definition

The amount outstanding of funds lent to other depository institutions, securities brokers, or securities dealers in the form of Federal Funds sold; for example, immediately available funds lent under agreements or contracts that mature in one business day or roll over under a continuing contract, regardless of the nature of the transaction or the collateral involved, excluding overnight lending for commercial and industrial purposes. Also include Federal Funds sold under agreements to resell on a gross basis, excluding (1) sales of term Federal Funds, (2) due bills representing purchases of securities or other assets by the reporting bank that have not yet been delivered and similar instruments, (3) resale agreements that mature in more than one business day involving assets other than securities, and (4) yield maintenance dollar repurchase agreements.

+ References

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- Details

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- Definition

Net long-term land leases which are capitalized as part of real property.

+ References

No definition available.

+ Details

Name:	us-gaap_GroundLeasesNet
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section 45

-Paragraph 4

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-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.2)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.8)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 8

-Article 5

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 20

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=29638263&loc=d3e39828-111592

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

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-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Article 9

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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