v3.25.2
Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Derivatives, Fair Value [Line Items]    
Accrued interest receivable $ 20,600 $ 22,100
Interest rate swaps | Derivatives Designated as Hedging Instruments | Other assets    
Derivatives, Fair Value [Line Items]    
Interest rate cash flow hedge asset at fair value [1] 279 1,529
Interest rate fair value hedge asset at fair value 179 1,477
Accrued interest receivable 79 120
Interest rate swaps | Derivatives Designated as Hedging Instruments | Other liabilities    
Derivatives, Fair Value [Line Items]    
Interest rate cash flow hedge liability at fair value [1] 1,011 229
Interest rate fair value hedge liability at fair value 0 0
Accrued interest payable 0 0
Interest rate swaps | Derivatives Designated as Hedging Instruments | Cash Flow Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Notional amount 120,000 120,000
Interest rate swaps | Derivatives Designated as Hedging Instruments | Fair Value Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Notional amount 100,000 100,000
Interest rate collar | Derivatives Designated as Hedging Instruments | Other assets    
Derivatives, Fair Value [Line Items]    
Interest rate cash flow hedge asset at fair value 0 0
Interest rate collar | Derivatives Designated as Hedging Instruments | Other liabilities    
Derivatives, Fair Value [Line Items]    
Interest rate cash flow hedge liability at fair value 63 30
Interest rate collar | Derivatives Designated as Hedging Instruments | Cash Flow Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Notional amount 100,000 50,000
Interest rate contracts with customers | Derivatives Not Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Notional amount 856,539 886,912
Interest rate contracts with customers | Derivatives Not Designated as Hedging Instruments | Other assets    
Derivatives, Fair Value [Line Items]    
Derivative assets not designated 6,134 2,468
Interest rate contracts with customers | Derivatives Not Designated as Hedging Instruments | Other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative liabilities not designated 32,834 51,372
Mirror interest rate contracts with counterparties | Derivatives Not Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Notional amount 856,539 886,912
Mirror interest rate contracts with counterparties | Derivatives Not Designated as Hedging Instruments | Other assets    
Derivatives, Fair Value [Line Items]    
Derivative assets not designated 32,710 51,176
Mirror interest rate contracts with counterparties | Derivatives Not Designated as Hedging Instruments | Other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative liabilities not designated 6,221 2,529
Risk participation agreements | Derivatives Not Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Notional amount 322,425 343,935
Risk participation agreements | Derivatives Not Designated as Hedging Instruments | Other assets    
Derivatives, Fair Value [Line Items]    
Derivative assets not designated 37 29
Risk participation agreements | Derivatives Not Designated as Hedging Instruments | Other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative liabilities not designated 0 0
Interest rate lock commitments | Derivatives Not Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Notional amount 37,232 20,238
Interest rate lock commitments | Derivatives Not Designated as Hedging Instruments | Other assets    
Derivatives, Fair Value [Line Items]    
Derivative assets not designated 785 248
Interest rate lock commitments | Derivatives Not Designated as Hedging Instruments | Other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative liabilities not designated 23 0
Forward sale commitments | Derivatives Not Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Notional amount 84,050 52,100
Forward sale commitments | Derivatives Not Designated as Hedging Instruments | Other assets    
Derivatives, Fair Value [Line Items]    
Derivative assets not designated 4 163
Forward sale commitments | Derivatives Not Designated as Hedging Instruments | Other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative liabilities not designated 1,012 291
Derivative assets    
Derivatives, Fair Value [Line Items]    
Gross derivative asset positions 40,128 57,090
Less: derivative asset amounts offset [2] 6,500 2,788
Derivative asset balances, net of offset 33,628 54,302
Less: collateral pledged, assets [3] 0 0
Net amounts 33,628 54,302
Derivative liabilities    
Derivatives, Fair Value [Line Items]    
Gross derivative liability positions 41,164 54,451
Less: derivative liability amounts offset [2] 6,500 2,788
Derivative liability balances, net of offset 34,664 51,663
Less: collateral pledged, liabilities [3] 0 0
Net amounts $ 34,664 $ 51,663
[1] The fair value of derivative assets includes accrued interest receivable of $79 thousand and $120 thousand, respectively, at June 30, 2025 and December 31, 2024. There was no accrued interest payable included in the fair value of derivative liabilities at June 30, 2025 or at December 31, 2024.
[2] Interest rate risk management contracts and loan related derivative contracts with counterparties are subject to master netting arrangements.
[3] Collateral contractually required to be pledged to derivative counterparties is in the form of cash. Washington Trust may need to post additional collateral in the future in proportion to potential increases in unrealized loss positions.