Securities Securities - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Securities pledged as collateral to secure public funds and other deposits or securities sold under agreements to repurchase	$ 1,231,000,000
Secured borrowing under agreement to repurchase	100,698,000
Accumulated unrealized losses	24,094,000		$ 59,594,000
Fair value of securities	1,609,257,000		$ 2,509,189,000
Debt Securities Available-for-sale Sold Amount	126,600,000
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	(1,448,000)	$ 22,000
Securities pledged as collateral
Debt Securities, Available-for-sale [Line Items]
Secured borrowing under agreement to repurchase	$ 100,698,000

Amount of investment in debt security, measured at fair value, sold.

No definition available.

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

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- Definition

The fair value as of the balance sheet date of financial instruments and other positions owned by the entity and pledged to counterparties as collateral, including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities.

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- Definition

Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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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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- Definition

Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral and funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

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