Activity in Accretable Yield Related to PCI loans, by Acquisition (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	$ 23,793	$ 15,640	$ 24,243
Additions	2	293	429
Accretion	(9,171)	(8,302)	(8,247)
Reclassifications from (to) nonaccretable difference	7,847	18,341	3,300
Other changes, net	7,227	(2,179)	(4,085)
Accretable yield, Ending Balance	29,698	23,793	15,640
Peoples
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	4,745	5,294	2,342
Additions		267	148
Accretion	(2,712)	(2,147)	(1,840)
Reclassifications from (to) nonaccretable difference	1,283	1,912	6,155
Other changes, net	273	(581)	(1,511)
Accretable yield, Ending Balance	3,589	4,745	5,294
Waccamaw Bank
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	19,048	10,338	21,886
Additions	2	26	281
Accretion	(6,459)	(6,118)	(6,288)
Reclassifications from (to) nonaccretable difference	6,564	16,400	(2,967)
Other changes, net	6,954	(1,598)	(2,574)
Accretable yield, Ending Balance	$ 26,109	19,048	10,338
Other
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance		8	15
Accretion		(37)	(119)
Reclassifications from (to) nonaccretable difference		$ 29	112
Accretable yield, Ending Balance			$ 8

Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield, Other Changes, Net

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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- Definition

Amount of decrease from accretion 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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- Definition

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

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

+ References

No definition available.

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- Definition

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.

+ References

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