Investment securities available for sale transferred to held to maturity amortized cost at date of transfer.

No definition available.

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- Definition

Investment securities available for sale transferred to held to maturity fair value at date of transfer.

+ References

No definition available.

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- Definition

Other Comprehensive Income Loss Unrealized Losses On Securities Available For Sale Transferred To Held To Maturity Arising During Period Before Tax

+ References

No definition available.

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- Definition

Unrealized Losses Related to Marketability of Securities or Issuer's Ability to Honor Redemption Obligations

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No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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 that have been in a continuous loss position for twelve months or longer.

+ References

No definition available.

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer.

+ References

No definition available.

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- Definition

Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

No definition available.

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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No definition available.

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
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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.

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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.

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No definition available.

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Investments (Narrative) (Details)	3 Months Ended		6 Months Ended
Investments (Narrative) (Details)	Jun. 30, 2018 USD ($) investments	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) investments	Jun. 30, 2017 USD ($)	May 01, 2018 USD ($)	Dec. 31, 2017 USD ($)
Schedule of Investments [Line Items]
Marketable equity securities	$ 107,264,000		$ 107,264,000			$ 0
Unrealized Losses Related to Marketability of Securities or Issuer's Ability to Honor Redemption Obligations	0		0			0
Fair Value, 12 months or more in unrealized loss position	661,241,000		661,241,000			2,975,631,000
Unrealized Losses, Greater than 12 months	21,136,000		21,136,000			59,470,000
Investment value deemed to be OTTI	0	$ 0
Investment securities, aggregate carrying value, pledged as collateral	3,670,000,000		3,670,000,000			4,590,000,000
Investment securities available for sale	4,783,507,000		4,783,507,000			7,180,180,000
Unrealized losses on available for sale securities transferred to held to maturity included in comprehensive income	(109,507,000)	$ 0	(109,507,000)	$ 0
Equity Securities
Schedule of Investments [Line Items]
Investment securities available for sale	0		0			105,208,000
Mortgage Backed Securities
Schedule of Investments [Line Items]
Fair Value, 12 months or more in unrealized loss position	654,212,000		654,212,000			2,723,406,000
Unrealized Losses, Greater than 12 months	$ 21,107,000		$ 21,107,000			59,241,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year \| investments	119		119
Investment securities available for sale	$ 3,034,065,000		$ 3,034,065,000			5,340,756,000
Investment securities available for sale transferred to held to maturity amortized cost					$ 2,490,000,000
Investment securities available for sale transferred to held to maturity fair value					$ 2,380,000,000
U. S. Treasury
Schedule of Investments [Line Items]
Fair Value, 12 months or more in unrealized loss position	0		0			249,698,000
Unrealized Losses, Greater than 12 months	0		0			201,000
Investment securities available for sale	1,503,974,000		1,503,974,000			1,657,864,000
Corporate Bonds
Schedule of Investments [Line Items]
Fair Value, 12 months or more in unrealized loss position	5,025,000		5,025,000
Unrealized Losses, Greater than 12 months	$ 2,000		$ 2,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year \| investments	1		1
Investment securities available for sale	$ 108,790,000		$ 108,790,000			$ 59,963,000
Financial Instruments ASU cumulative effect adjustment
Schedule of Investments [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption	$ 18,700,000		$ 18,700,000