Summary of Significant Accounting Policies - Operations, Segments (Details)	12 Months Ended
Dec. 31, 2020 USD ($) item subsidiary segment
Nature of Operations
Number of unconsolidated subsidiaries \| subsidiary	20
Segments
Number of Operating Segments \| segment	1
Investment in unconsolidated subsidiaries
Nature of Operations
Trust preferred securities to be issued \| $	$ 153,500,000
South Carolina
Nature of Operations
Number of counties	28
NORTH CAROLINA
Nature of Operations
Number of counties \| $	9
VIRGINIA
Nature of Operations
Number of counties	4
ALABAMA
Nature of Operations
Number of counties	5
GEORGIA
Nature of Operations
Number of counties	25
FLORIDA
Nature of Operations
Number of counties \| $	32

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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Balance Type:	na
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