Derivatives and Balance Sheet Offsetting - Fair value of derivatives & classifications table (Details) - Not Designated as Hedging Instrument [Member] - Interest Rate Contracts [Member] - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Fair value of asset derivative instruments	$ 32,546	$ 46,184
Fair value of liability derivative instruments	32,853	46,637
Other Assets [Member] | Interest Rate Lock Commitments Contracts
Derivative [Line Items]
Fair value of asset derivative instruments	585	1,096
Other Assets [Member] | Interest rate Forward Sales Contracts
Derivative [Line Items]
Fair value of asset derivative instruments	0	0
Other Assets [Member] | Interest Rate Swap Contracts
Derivative [Line Items]
Fair value of asset derivative instruments	32,546	46,184
Other Liabilities [Member] | Interest Rate Lock Commitments Contracts
Derivative [Line Items]
Fair value of liability derivative instruments	0	0
Other Liabilities [Member] | Interest rate Forward Sales Contracts
Derivative [Line Items]
Fair value of liability derivative instruments	23	165
Other Liabilities [Member] | Interest Rate Swap Contracts
Derivative [Line Items]
Fair value of liability derivative instruments	$ 32,853	$ 46,637