Fair Value Schedule of qualitative information on Level 3 measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans carried at fair value	$ 2,090	$ 6,399
Other Assets, Fair Value Disclosure	6,426,869	5,570,136
Nonrecurring basis
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other Assets, Fair Value Disclosure	3,033	3,674
Nonrecurring basis | Residential real estate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other Assets, Fair Value Disclosure	738	650
Loans | Nonrecurring basis | Commercial Real Estate Portfolio Segment [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans carried at fair value	1,873	4,059
Loans | Nonrecurring basis | Residential real estate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans carried at fair value	217	705
Loans | Nonrecurring basis | Construction Real Estate Remaining Commercial [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans carried at fair value		1,635
Other real estate owned | Nonrecurring basis | Other Real Estate Owned, Commercial [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other Assets, Fair Value Disclosure	2,295	2,295
Other real estate owned | Nonrecurring basis | Other Real Estate Owned, Residential [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other Assets, Fair Value Disclosure	$ 738	650
Other real estate owned | Nonrecurring basis | Other Real Estate Owned, Construction [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other Assets, Fair Value Disclosure		$ 729