XML 66 R54.htm IDEA: XBRL DOCUMENT
v3.24.1.u1

Derivative Instruments and Hedging Activities - Effect of Fair Value Hedges on Consolidated Statements of Income (Details) - Derivatives not designated as hedging instruments - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Derivative [Line Items] |  |
Gain (Loss) Recognized in Consolidated Statements of Income | $ 1,421 | $ 1,331
Interest rate contracts |  |
Derivative [Line Items] |  |
Gain (Loss) Recognized in Consolidated Statements of Income | (160) | 18
Mortgage derivatives | Mortgage derivatives - interest rate lock commitments |  |
Derivative [Line Items] |  |
Gain (Loss) Recognized in Consolidated Statements of Income | 400 | 1,109
Mortgage derivatives | Mortgage derivatives - forward commitments to sell fixed-rate mortgage loans |  |
Derivative [Line Items] |  |
Gain (Loss) Recognized in Consolidated Statements of Income | 462 | (328)
Risk participation agreements |  |
Derivative [Line Items] |  |
Gain (Loss) Recognized in Consolidated Statements of Income | (1) | 3
Foreign exchange contracts |  |
Derivative [Line Items] |  |
Gain (Loss) Recognized in Consolidated Statements of Income | $ 720 | $ 529

X
- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A + Details
Name: | us-gaap_DerivativeGainLossOnDerivativeNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480237/815-40-50-5 + Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_NondesignatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=syn_MortgageDerivativeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_InterestRateLockCommitmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=syn_ForwardCommitmentsToSellFixedRateMortgageLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=syn_RiskParticipationAgreementsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |