Estimated Fair Values (Narrative) (Details)	3 Months Ended
	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers from level 2 to level 3	$ 0	$ 1,800,000
Gains (Losses) from fair value changes on originated loans held for sale	(2,700,000)	$ 1,200,000
Originated loans held for sale, 90 days or more past due	0		$ 0
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability measured at fair value on nonrecurring basis	$ 0		$ 0
Discount Rate | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.06
OREO, measurement input	0.06
Discount Rate | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.10
OREO, measurement input	0.15
Discount Rate | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale, measurement input	0.0681
OREO, measurement input	0.0876