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Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of deposits held by the entity that have been reclassified as loan balances receivable, for example, but not limited to, overdrafts receivable.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties.

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Loans (Details) - USD ($)	12 Months Ended
Loans (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Apr. 01, 2019	Jul. 01, 2018
Financing Receivable, Impaired [Line Items]
Loans and Leases Receivable, Deferred Income	$ 16,300,000	$ 12,500,000
Goodwill, Purchase Accounting Adjustments	(3,373,000)	(793,000)	$ 0
Deposit Liabilities Reclassified as Loans Receivable	2,200,000	2,300,000
Business Combination, Acquired Receivables, Gross Contractual Amount				$ 589,698,000	$ 277,919,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables				578,577,000	272,753,000
Business Combination, Acquired Receivable, Fair Value				578,577,000	272,753,000
Executive officers and directors
Financing Receivable, Impaired [Line Items]
Loans due from related party	44,300,000	35,900,000
Loans and Leases Receivable, Related Parties, Additions	9,200,000	1,400,000
Increase (Decrease) in Customer Advances	8,900,000	4,900,000
Loans and Leases Receivable, Related Parties, Proceeds	15,300,000	11,500,000
Executive officers and directors \| Loans
Financing Receivable, Impaired [Line Items]
Loans due from related party	28,700,000	25,900,000
Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable, Impaired [Line Items]
Business Combination, Acquired Receivables, Gross Contractual Amount	3,200,000	4,600,000			5,100,000
Business Combination, Acquired Receivable, Fair Value	3,000,000.0	4,400,000			$ 4,900,000
Financial Asset Acquired with Credit Deterioration [Member] \| NewDominion [Member]
Financing Receivable, Impaired [Line Items]
Allowance for Loan and Lease Losses, Loans Acquired	101,000	0
Financial Asset Acquired with Credit Deterioration [Member] \| Carolina Alliance [Member]
Financing Receivable, Impaired [Line Items]
Business Combination, Acquired Receivables, Gross Contractual Amount	13,800,000			19,900,000
Business Combination, Acquired Receivable, Fair Value				$ 18,400,000
Allowance for Loan and Lease Losses, Loans Acquired	167,000
Loans
Financing Receivable, Impaired [Line Items]
Goodwill, Purchase Accounting Adjustments	$ 11,700,000	$ 4,400,000