Acquisition (Details) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended
	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Sep. 30, 2018 USD ($) shares	May 31, 2018 USD ($) $ / shares	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares			3,253,060
Assets	$ 1,620,299		$ 1,620,299		$ 1,295,638
Interest-bearing demand deposits	3,676		3,676		4,227
Liabilities	1,406,784		1,406,784		1,145,367
Deposits	1,371,023		1,371,023		1,085,821
Goodwill	59,287		59,287		$ 30,183	$ 30,183	$ 30,183
Business Acquisition, Share Price | $ / shares				$ 0.1955
Columbus First Bancorp, Inc. [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Less common stock issued	63,598	$ 63,598	63,598
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Equity Interests	0
Less cash paid for the common stock		783	783
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Payments To Acquire Business, Gross	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	13,679	13,679	13,679
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Cash and Equivalents	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Assets	10,350	10,350	10,350
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Assets	0
Number of branches				1
Equity interest exchange ratio				2
Business combination, consideration transferred		64,381	64,381
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Federal Home Loan Bank Stock	1,207	1,207	1,207
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Federal Home Loan Bank Stock	0
Business Combination, Acquired Receivable, Fair Value	282,133	282,748	282,133	$ 279,838
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Loans Receivable	(615)
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Loan Receivables Held For Sale	1,819	1,819	1,819
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Loan Receivables Held For Sale	0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	102	102	102
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	2,177	2,089	2,177
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	88
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Real Estate Owned	35	35	35
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other Real Estate Owned	0
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	352	0	352
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Tax Assets	352
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	1,306	2,022	1,306
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other Noncurrent Assets	(716)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	313,160	314,051	313,160
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Assumed Assets	(891)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities	244,430	245,036	244,430
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities	(606)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt	22,943	22,920	22,943
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Current Liabilities, Long-Term Debt	23
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Short-term Borrowings	10,000	10,000	10,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Current Liabilities, Short-Term Borrowings	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent	0	200	0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Tax Liabilities	(200)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	510	491	510
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Noncurrent Liabilities, Other	19
Liabilities assumed	277,883	278,647	277,883
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Assumed Liabilities	(764)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	35,277	35,404	35,277
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Recognized Identifiable Assets Acquired And Liabilities Assumed, Net	(127)
Goodwill	29,104	$ 28,977	$ 29,104
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Goodwill	$ 127