Activity in Accretable Yield Related to PCI loans, by Acquisition (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	$ 15,640	$ 24,243	$ 919
Additions	293	429	29,881
Accretion	(8,302)	(8,247)	(5,260)
Reclassifications from (to) nonaccretable difference	18,341	3,300	185
Disposals	(2,179)	(4,085)	(1,482)
Accretable yield, Ending Balance	23,793	15,640	24,243
Peoples
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	5,294	2,342
Additions	267	148	3,400
Accretion	(2,147)	(1,840)	(856)
Reclassifications from (to) nonaccretable difference	1,912	6,155
Disposals	(581)	(1,511)	(202)
Accretable yield, Ending Balance	4,745	5,294	2,342
Waccamaw Bank
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	10,338	21,886
Additions	26	281	26,481
Accretion	(6,118)	(6,288)	(3,315)
Reclassifications from (to) nonaccretable difference	16,400	(2,967)
Disposals	(1,598)	(2,574)	(1,280)
Accretable yield, Ending Balance	19,048	10,338	21,886
Other
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, accretable Yield
Accretable yield, Beginning Balance	8	15	919
Accretion	(37)	(119)	(1,089)
Reclassifications from (to) nonaccretable difference	29	112	185
Accretable yield, Ending Balance		$ 8	$ 15

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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