Loans and Asset Quality Information (Changes in Recorded Investment and Accretable Yield of PCI Loans) (Details) - Purchased Credit Impaired Loans - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
PCI Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period	$ 17,393	$ 23,165	$ 514
Accretion	(4,863)	(5,799)	(6,016)
Change due to loan charge-offs	(11)	(4)	(12)
Transfers to foreclosed real estate	0	(10)	(69)
Other, net	145	41	(392)
Balance at end of period	12,664	17,393	23,165
PCI Loans, Accretable Discount
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period	4,750	4,688	0
Accretion	(1,486)	(2,050)	(1,846)
Reclassification from (to) nonaccretable difference	617	849	423
Other, net	268	1,263	690
Balance at end of period	4,149	4,750	4,688
Carolina Bank \| PCI Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Additions	0	0	19,254
Carolina Bank \| PCI Loans, Accretable Discount
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Additions	0	0	3,617
Asheville Savings Bank \| PCI Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Additions	0	0	9,886
Asheville Savings Bank \| PCI Loans, Accretable Discount
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Additions	$ 0	$ 0	$ 1,804

Certain Loans Acquired In Transfer Not Accounted For As Debt Securities, Accretable Yield, Other

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- Definition

Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
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-Publisher FASB
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-Section 50
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- Definition

Amount of accretion recognized for the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities, with evidence of deterioration of credit quality.

+ References

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Amount of additions to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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- Definition

Amount of reduction, resulting from a sale or transfer of a loan, in the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 30
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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Amount of reclassification (to) from nonaccretable difference (from) to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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- Definition

Amount of reduction, resulting from a reclassification to held-for-sale, in the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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