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Business and Summary of Significant Accounting Policies (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Feb. 28, 2018 USD ($)
Accounting Policy [Line Items]
Equity Method Investment, Ownership Percentage		100.00%
Marketable Securities, Unrealized Gain (Loss)		$ 50,000
Financing Receivable, Individually Evaluated for Impairment		6,926,000	$ 13,590,000	$ 20,254,000
Goodwill impairment		$ 0	0	0
BOLI single carrier percentage of Tier I capital		15.00%
BOLI CSV percentage of Tier I Capital		25.00%
Number of Reporting Unit Levels		1
Interest Expense, Cash Rewards, Deposits		$ 438,000
Held-to-maturity Securities, Transferred Security, at Carrying Value			92,000,000
Loans Held-for-sale		4,403,000	8,103,000
HTM securities		1,307,000	94,073,000
AFS securities		$ 910,692,000	789,899,000
Stockholders' Equity Note, Stock Split, Conversion Ratio	1.5	1.5
Minimum [Member]
Accounting Policy [Line Items]
Financing Receivable, Individually Evaluated for Impairment		$ 500,000
Finite-lived intangible asset, useful life (years)		5 years
Maximum [Member]
Accounting Policy [Line Items]
Finite-lived intangible asset, useful life (years)		10 years
Residential real estate
Accounting Policy [Line Items]
Financing Receivable, Individually Evaluated for Impairment		$ 4,762,000	5,171,000	$ 4,348,000
Retained Earnings [Member]
Accounting Policy [Line Items]
Reclassification adjustment			(198,000)
Retained Earnings [Member] | Accounting Standards Update 2018-02 [Member]
Accounting Policy [Line Items]
Reclassification adjustment					$ 3,500,000
AOCI Attributable to Parent [Member]
Accounting Policy [Line Items]
Reclassification adjustment			$ 198,000
AOCI Attributable to Parent [Member] | Accounting Standards Update 2018-02 [Member]
Accounting Policy [Line Items]
Reclassification adjustment					$ 3,500,000

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