Not applicable.

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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.

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No definition available.

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

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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.

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No definition available.

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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.

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No definition available.

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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.

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No definition available.

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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.

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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.

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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.

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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.

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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.

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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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No definition available.

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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.

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

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

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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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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.

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No definition available.

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Loan Servicing, Mortgage Origination, and Loans Held for Sale (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
MSRs
Changes in the fair value of MSRs and its offsetting hedge.
Increase (decrease) in fair value of MSRs	$ 1,020	$ (2,294)	$ (9,078)	$ (7,218)
Decay of MSRs	(2,391)	(1,312)	(5,590)	(3,341)
Gain related to derivatives	619	1,476	10,915	5,415
Net effect on statements of income	(752)	(2,130)	$ (3,753)	$ (5,144)
Characteristics and sensitivity analysis of the MSR
Composition of residential loans serviced for others						100.00%	100.00%	100.00%
Weighted average life (in years)			5 years 6 months 7 days	6 years 1 month 6 days	6 years 6 months 18 days
Constant Prepayment rate (CPR) (as a percent)			14.30%	11.40%	10.30%
Weighted average discount rate (as a percent)			9.00%	9.40%	9.40%
Effect on fair value due to change in interest rates:
25 basis point increase						$ 2,533	$ 2,477	$ 2,398
50 basis point increase						5,178	4,452	4,390
25 basis point decrease						(2,400)	(2,938)	(2,862)
50 basis point decrease						(3,665)	$ (6,228)	(5,999)
Custodial escrow balances maintained in connection with the loan servicing						$ 48,100		$ 33,700
Fixed-rate mortgage loans
Characteristics and sensitivity analysis of the MSR
Composition of residential loans serviced for others						99.90%	99.80%	99.80%
Adjustable-rate mortgage loans
Characteristics and sensitivity analysis of the MSR
Composition of residential loans serviced for others						0.10%	0.20%	0.20%
First Financial Holdings, Inc. ("First Financial")
Loans held for sale, loan servicing and mortgage origination
Residential mortgages serviced for others						$ 4,500,000	$ 3,300,000	$ 3,100,000
Contractually specified servicing fees earned	2,500	1,900	$ 6,800	$ 5,800
First Financial Holdings, Inc. ("First Financial") \| MSRs
Loans held for sale, loan servicing and mortgage origination
Mortgage servicing rights	34,600	28,700	30,500	28,700	$ 30,500	$ 34,600	$ 30,500	$ 28,700
Analysis of the activity in the MSRs
Balance at beginning of the period			30,500
Balance at end of period	$ 34,600	$ 28,700	$ 34,600	$ 28,700	$ 30,500