The unallocated amount of allowance to cover probable credit losses on loans and leases.

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The number of states the entity operates in as of the balance sheet date.

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Represents the period from due date after which accrual of interest income is discontinued when full loan repayment is in doubt or when a loan becomes contractually past due.

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No definition available.

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The aggregate expected value at the end of their useful life of a major finite-lived intangible asset class acquired during the period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Summary of Significant Accounting Policies - Dividend (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) segment item	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 21, 2020 $ / shares
90-Days or Greater Past Due Loans
Period from due date after which accrual of interest income is discontinued	90 days
Goodwill and Core Deposit Intangible
Impairment of goodwill	$ 0
Amortization of core deposit intangible	$ 539,000	$ 387,000	$ 96,000
Subsequent Events
Number of banking centres \| item	29
Operating segment \| segment	1
Core Deposits [Member]
Goodwill and Core Deposit Intangible
Amortization of core deposit intangible	$ 539,000	387,000	96,000
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2020	494,000
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2021	459,000
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2022	421,000
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2023	379,000
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2024	331,000
Core Deposits [Member] \| Talmer
Goodwill and Core Deposit Intangible
Remaining intangible asset	$ 366,000
Core Deposits [Member] \| GCFC/ABC Bank
Goodwill and Core Deposit Intangible
Useful life (in years)	10 years
Intangible asset recorded	$ 3,100,000
Remaining intangible asset	2,300,000
Subsequent Event
Subsequent Events
Dividends Payable, Amount Per Share \| $ / shares				$ 0.01
Unallocated Financing Receivables [Member]
Allowance for Loan Losses
Unallocated component of allowance	$ 503,000	$ 537,000	$ 542,000