Not applicable.

No definition available.

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The amounts related to derivatives that offset the gain (loss) on changes of the fair value financial instruments.

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No definition available.

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Represents the value of residential mortgages serviced for others, which are acquired through merger transaction.

+ References

No definition available.

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Represents the percentage of residential mortgages serviced for others, which are acquired through merger transaction.

+ References

No definition available.

+ Details

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- Definition

The hypothetical financial impact of a 25 basis point decrease in interest rates on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The hypothetical financial impact of a 25 basis point increase in interest rates on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The hypothetical financial impact of a 50 basis point decrease in interest rates on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

No definition available.

+ Details

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The hypothetical financial impact of a 50 basis point increase in interest rates on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

No definition available.

+ Details

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- References

No definition available.

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All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746

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- Definition

The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10)
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- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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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.

+ Details

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Amount of increase (decrease) in fair value from changes classified as other for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(5)
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- Definition

The increase (decrease) in the fair value of servicing assets that are subsequently measured at fair value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)
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- References

No definition available.

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Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (d)
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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746

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- Definition

Weighted average life of financial assets and financial liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (d)
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Loan Servicing, Mortgage Origination, and Loans Held for Sale (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017
Loans held for sale, loan servicing and mortgage origination
Mortgage servicing rights				$ 34,196	$ 31,119	$ 30,063
MSRs
Changes in the fair value of MSRs and its offsetting hedge.
Increase (decrease) in fair value of MSRs	$ 2,516	$ 444
Decay of MSRs	(929)	(803)
Gains (losses) related to derivatives	(1,554)	266
Net effect on Statements of Income	$ 33	$ (93)
Characteristics and sensitivity analysis of the MSR
Residential Mortgages Serviced for Others Percentage				100.00%	100.00%	100.00%
Weighted average life	8 years 5 months 12 days	7 years 8 months 5 days	7 years 7 months 21 days
Constant prepayment rate (as a percent)	6.30%	7.80%	7.70%
Weighted average discount rate (as a percent)	9.60%	9.80%	9.60%
Effect on fair value due to change in interest rates:
25 basis point increase				$ 1,025	$ 1,485	$ 1,375
50 basis point increase				1,791	2,664	2,431
25 basis point decrease				(1,439)	(1,850)	(1,746)
50 basis point decrease				(3,189)	$ (4,014)	(3,774)
Custodial escrow balances maintained in connection with the loan servicing				$ 20,900		$ 18,200
Fixed-rate mortgage loans
Characteristics and sensitivity analysis of the MSR
Residential Mortgages Serviced for Others Percentage				99.70%	99.70%	99.60%
Adjustable-rate mortgage loans
Characteristics and sensitivity analysis of the MSR
Residential Mortgages Serviced for Others Percentage				0.30%	0.30%	0.40%
First Financial Holdings, Inc. ("First Financial")
Loans held for sale, loan servicing and mortgage origination
Residential mortgages serviced for others				$ 3,000,000	$ 2,900,000	$ 2,800,000
Contractually specified servicing fees earned	$ 1,900	$ 1,800
First Financial Holdings, Inc. ("First Financial") \| MSRs
Loans held for sale, loan servicing and mortgage origination
Mortgage servicing rights	31,100	30,100	$ 31,100	$ 34,200	$ 31,100	$ 30,100
Analysis of the activity in the MSRs
Balance at beginning of the period	31,100
Balance at end of period	$ 34,200	$ 30,100	$ 31,100