Mortgage Banking Activities, Components of Loans Held For Sale (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Number of days for past due for a residential mortgage loan to be considered nonperforming (in days)	90 days	90 days
Residential mortgage loans held for sale, nonperforming	$ 0	$ 0
Credit losses recognized on residential mortgage loans held for sale	0	0
Components of Residential Mortgage Loans Held for Sale [Abstract]
Unpaid principal balance	145,057	212,525
Residential mortgage loans held for sale, Fair value	146,971	215,113
Total residential mortgages loans held for sale and mortgage loan commitments, net of forward sales contracts	$ 149,221	$ 221,378
Not Designated as Hedging Instrument [Member] | Residential mortgage loan commitments [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
General number of days outstanding for residential mortgage commitments, minimum (in days)	60 days	60 days
General number of days outstanding for residential mortgage commitments, maximum (in days)	90 days	90 days
Components of Residential Mortgage Loans Held for Sale [Abstract]
Notional	$ 160,848	$ 222,919
Derivative, Net fair value	$ 5,378	$ 6,523
Not Designated as Hedging Instrument [Member] | Forward sales contracts [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
General number of days for delivery of loans, for which the price is set by forward sales contracts, minimum (in days)	60 days	60 days
General number of days for delivery of loans, for which the price is set by forward sales contracts, maximum (in days)	90 days	90 days
Components of Residential Mortgage Loans Held for Sale [Abstract]
Notional	$ 274,000	$ 380,159
Derivative, Net fair value	$ (3,128)	$ (258)