Borrowings (Short-Term) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Short-term Debt [Line Items]
Short-term borrowings	$ 738,233	$ 572,287
Additional secured debt available	8,990,000
Securities sold under customer repurchase agreements
Short-term Debt [Line Items]
Short-term borrowings	442,956	543,936
Notes payable to FHLB of Atlanta
Short-term Debt [Line Items]
Short-term borrowings	255,000	28,500
Other short-term debt
Short-term Debt [Line Items]
Short-term borrowings	40,277	0
Unamortized purchase accounting adjustments
Short-term Debt [Line Items]
Short-term borrowings	0	$ (149)
Unsecured Debt
Short-term Debt [Line Items]
Accessible overnight borrowings	$ 582,700

Amount of advances or credit lines available from the FHLB and FRB.

No definition available.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

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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