Activity in Accretable Yield Related to PCI loans, by Acquisition (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	$ 23,793	$ 15,640
Additions	2	8
Accretion	(2,232)	(2,137)
Reclassifications from (to) nonaccretable difference	3,551	9,325
Removal events	(1,174)	(279)
Accretable yield, Ending Balance	23,940	22,557
Peoples
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	4,745	5,294
Additions		1
Accretion	(630)	(563)
Reclassifications from (to) nonaccretable difference	1,106	337
Removal events	(735)	(112)
Accretable yield, Ending Balance	4,486	4,957
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	7
Accretion	(1,602)	(1,563)
Reclassifications from (to) nonaccretable difference	2,445	8,977
Removal events	(439)	(167)
Accretable yield, Ending Balance	19,454	17,592
Other
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance		8
Accretion		(11)
Reclassifications from (to) nonaccretable difference		11
Accretable yield, Ending Balance		$ 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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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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