Carrying and Contractual Unpaid Principal Balance of PCI loans, by Acquisition (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal, ending balance		$ 16,660	$ 25,816
PCI loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, beginning balance	2,886	62,283	81,711
Impaired loans acquired	150,175
Carrying value, ending balance	141,340	62,283	81,711
Unpaid principal, ending balance	198,343	101,711	128,498
Peoples \| PCI loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, beginning balance		7,090	9,196
Impaired loans acquired	32,603
Carrying value, ending balance	26,907	7,090	9,196
Unpaid principal, ending balance	34,644	13,669	17,431
Waccamaw Bank \| PCI loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, beginning balance		53,835	70,584
Impaired loans acquired	117,572
Carrying value, ending balance	112,093	53,835	70,584
Unpaid principal, ending balance	157,781	86,641	105,677
Other \| PCI loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, beginning balance		1,358	1,931	2,886
Carrying value, ending balance	2,340	1,358	1,931	2,886
Unpaid principal, ending balance	$ 5,918	$ 1,401	$ 5,390

Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Acquired During Period Contractually Required Payment Receivable At Acquisition

No definition available.

+ Details

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were 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.

+ 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)(1)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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