Loan Servicing, Mortgage Origination, and Loans Held for Sale - Mandatory cash forwards - (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Loan sales	$ 154,900	$ 177,700
Loan securitizations and loan sales	$ 118,400	$ 120,600
Percentage of loan securitizations and loan sales	76.50%	67.90%
Loans held for sale	$ 42,690	$ 46,988	$ 70,890
Residential mortgage loans to be sold in secondary market
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Residential mortgage loans held for sale	42,700	47,000	45,500
Loans Held-for-sale, Mortgages	$ 42,700	$ 47,000	$ 45,500
Residential mortgage loans awaiting sale in secondary market \| Minimum
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Loans held for sale, settlement period	15 days
Residential mortgage loans awaiting sale in secondary market \| Maximum
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Loans held for sale, settlement period	45 days
Park Sterling Corporation
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Loans held for sale, commercial	$ 25,400

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No definition available.

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- Definition

Represents the amount of mortgage loan securitized and sold during the period.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Represents the amount of mortgage loan sold during the period.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of mortgage loan securitized and sold during the period with servicing rights retained by the company.

+ References

No definition available.

+ Details

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- Definition

Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

+ Details

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- Definition

Amount, after allowance for bad debt, of commercial and industrial loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

+ Details

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- Definition

Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

+ Details

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