Activity in Accretable Yield Related to PCI loans, by Acquisition (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	$ 23,793	$ 15,640
Additions	2	90
Accretion	(4,029)	(4,138)
Reclassifications from (to) nonaccretable difference	3,551	12,139
Removal events	(1,542)	(1,513)
Accretable yield, Ending Balance	21,775	22,218
Peoples
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	4,745	5,294
Additions	0	70
Accretion	(1,169)	(1,096)
Reclassifications from (to) nonaccretable difference	1,106	513
Removal events	(735)	(467)
Accretable yield, Ending Balance	3,947	4,314
Waccamaw Bank
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	19,048	10,338
Additions	2	20
Accretion	(2,860)	(3,019)
Reclassifications from (to) nonaccretable difference	2,445	11,603
Removal events	(807)	(1,046)
Accretable yield, Ending Balance	17,828	17,896
Other
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	0	8
Additions	0	0
Accretion	0	(23)
Reclassifications from (to) nonaccretable difference	0	23
Removal events	0	0
Accretable yield, Ending Balance	$ 0	$ 8

Sale or transfer of a loan during the period resulting in a reduction in the excess of a loan's cash flows expected to be collected over the investor's initial investment. This relates to loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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 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.

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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.

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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.

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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.

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