XML 54 R43.htm IDEA: XBRL DOCUMENT
v3.10.0.1

MARKETABLE SECURITIES - Sale of Securities (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Sale of Marketable Securities [Abstract] |  |  |  |
Proceeds | $ 9,457 | $ 14,762 | $ 9,457 | $ 14,762
Gross gains | 0 | 38 | 0 | 38
Gross losses | $ (51) | (13) | (51) | (13)
Held-to-maturity Securities, Sales, Excluding Other than Temporary Impairments [Abstract] |  |  |  |
Proceeds from sales |  | 923 | $ 0 | 923
Amortized cost |  | 907 |  | 907
Gross realized gains |  | 16 |  | 16
Tax expense related to securities gains/losses |  | $ (4) |  | $ (4)

X
- Definition Held-to-maturity Securities, Sold Security, Amortized Cost + References No definition available. + Details
Name: | gnty_HeldtomaturitySecuritiesSoldSecurityAmortizedCost
Namespace Prefix: | gnty_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Held-to-maturity Securities, Sold Security, Tax Expense (Benefit) On Realized Gain (Loss) + References No definition available. + Details
Name: | gnty_HeldtomaturitySecuritiesSoldSecurityTaxExpenseBenefitOnRealizedGainLoss
Namespace Prefix: | gnty_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Marketable Securities, Gross Realized Gains + References No definition available. + Details
Name: | gnty_MarketableSecuritiesGrossRealizedGains
Namespace Prefix: | gnty_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Marketable Securities, Gross Realized Losses + References No definition available. + Details
Name: | gnty_MarketableSecuritiesGrossRealizedLosses
Namespace Prefix: | gnty_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Proceeds from the Sale of Marketable Securities + References No definition available. + Details
Name: | gnty_ProceedsfromtheSaleofMarketableSecurities
Namespace Prefix: | gnty_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Sale Of Marketable Securities [Abstract] + References No definition available. + Details
Name: | gnty_SaleOfMarketableSecuritiesAbstract
Namespace Prefix: | gnty_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition This item represents the gain (loss) realized on the sale of held-to-maturity securities disposed of during the period. Additionally, this item may include, if not separately presented, any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt securities which are being or have been recognized in earnings during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27405-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesSoldSecurityRealizedGainLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_HeldtomaturitySecuritiesSalesExcludingOtherThanTemporaryImpairmentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26853-111562 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
Name: | us-gaap_ProceedsFromSaleOfHeldToMaturitySecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration