Investment Securities - Pledged Securities and Concentration Narrative (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Pledged securities
Total pledged securities	$ 2,400,000,000	$ 1,800,000,000
Securities pledged to secure public deposits	2,186,759,000	1,543,492,000
Securities pledged to secure other financial transactions	201,400,000	242,300,000
Non-government issuer
Concentration of risk
Securities of issuers in excess of 10% of stockholders' equity	$ 0	$ 0

The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for other financial transactions, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

No definition available.

+ Details

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- Definition

The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for public deposits, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13531-108611

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- Definition

Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- References

No definition available.

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