Qualified Affordable Housing And Historic Rehabilitation Projects (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Investments in Affordable Housing Projects [Abstract]
Investment in qualified affordable housing projects	$ 5,000,000.0		$ 5,000,000.0		$ 6,000,000.0
Amortization expense included in noninterest expense	700,000	$ 700,000	2,000,000.0	$ 2,000,000
Affordable housing tax credits	700,000	$ 800,000	2,200,000	$ 2,300,000
Investment in historic rehabilitation projects	1,100,000		1,100,000		300,000
Historic rehabilitation tax credits	$ 300,000		$ 900,000		$ 0