Business Combinations - United American(Details)	May 04, 2018 USD ($) $ / shares shares	Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2017 USD ($)
Business Combinations
Stock price (in dollars per share) | $ / shares	$ 16.73
Assets acquired:
Securities available-for-sale		$ 63,723,000
Net loans		336,446,000
Premises and equipment, net		350,000
Other assets, net		15,016,000
Liabilities assumed:
Deposits		416,628,000
Other borrowings		62,000
Other liabilities		3,030,000
Goodwill recorded in the merger		$ 84,417,000	$ 45,664,000	$ 45,664,000
United American Bank
Business Combinations
Aggregate transaction value	$ 56,417,000
Fixed exchange ratio of company's common stock	2.1644
Shares issued in acquisition | shares	2,826,032
Total cash paid	$ 9,137,000
Issuance of 2,826,032 shares of common stock to United American shareholders at $16.73 per share	47,280,000
Total Consideration Paid	56,417,000
Loan participations repurchase	$ 23,732,000
Amortized intangible assests	3 years
Assets acquired:
Cash and cash equivalents	$ 13,118,000
Securities available-for-sale	63,723,000
Net loans	215,477,000
Other intangible assets	5,431,000
Other assets, net	8,321,000
Total assets acquired	306,070,000
Liabilities assumed:
Deposits	281,240,000
Other borrowings	62,000
Other liabilities	2,422,000
Total liabilities assumed	283,724,000
Net assets acquired	22,346,000
Purchase price	47,280,000
Goodwill recorded in the merger	24,934,000
United American Bank | As Recorded
Assets acquired:
Cash and cash equivalents	45,638,000
Securities available-for-sale	64,144,000
Net loans	196,694,000
Allowance for loan losses	(2,952,000)
Other assets, net	9,119,000
Total assets acquired	312,643,000
Liabilities assumed:
Deposits	281,189,000
Other borrowings	62,000
Other liabilities	2,617,000
Total liabilities assumed	283,868,000
United American Bank | Fair Value Adjustments
Assets acquired:
Cash and cash equivalents	(32,520,000)
Securities available-for-sale	(421,000)
Net loans	18,783,000
Allowance for loan losses	2,952,000
Other intangible assets	5,431,000
Other assets, net	(798,000)
Total assets acquired	(6,573,000)
Liabilities assumed:
Deposits	51,000
Other liabilities	(195,000)
Total liabilities assumed	(144,000)
Series A Preferred Stock | United American Bank
Business Combinations
Total cash paid	8,700,000
Series B Preferred Stock | United American Bank
Business Combinations
Total cash paid	$ 435,000
Series A and Series B Preferred Stock | United American Bank
Business Combinations
Cash issued per share | $ / shares	$ 1,000
Other | United American Bank
Business Combinations
Total cash paid	$ 2,000