Depository Shares Issued

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- Definition

Depository Shares Issued, Price Per Share

+ References

No definition available.

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- Definition

Depository Shares to Preferred Stock Ratio

+ References

No definition available.

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- Definition

Related Party Transaction, Expenses from Transactions with Related Party, Net

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

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- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

+ References

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-Publisher FASB
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-SubTopic 10
-Section 50
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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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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- Definition

Number of new stock issued during the period.

+ References

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-Topic 210
-SubTopic 10
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RELATED-PARTY TRANSACTIONS - Transactions Involving Underwriting Services (Details) - USD ($)	Oct. 27, 2016	Mar. 08, 2016	Feb. 08, 2016	Apr. 08, 2015	Apr. 06, 2015	Mar. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Expenses from transactions with related parties					$ 263,000
Expenses from transactions with related parties, net of related expenses					221,000
Preferred stock, liquidation preference per share (in dollars per share)						$ 1,000
Par Value						$ 175,000,000	$ 175,000,000
Senior Notes \| 5.25% Senior Notes Due April 15, 2025
Related Party Transaction [Line Items]
Par Value					$ 175,000,000	$ 175,000,000	$ 175,000,000
Stated interest rate					5.25%	5.25%
Series E 7.00% non-cumulative perpetual
Related Party Transaction [Line Items]
Non cumulative preferred stock, dividend rate			7.00%
Series D 7.375% non-cumulative perpetual
Related Party Transaction [Line Items]
Non cumulative preferred stock, dividend rate				7.375%
Underwritten Public Offering
Related Party Transaction [Line Items]
Depository shares issued (in shares)			5,000,000	4,600,000
Offering price per share (in dollars per share)			$ 25	$ 25
Underwritten Public Offering \| Series E 7.00% non-cumulative perpetual
Related Party Transaction [Line Items]
Depository shares to preferred stock ratio			2.50%
Preferred stock, liquidation preference per share (in dollars per share)			$ 1,000
Underwritten Public Offering \| Series D 7.375% non-cumulative perpetual
Related Party Transaction [Line Items]
Depository shares to preferred stock ratio				2.50%
Preferred stock, liquidation preference per share (in dollars per share)				$ 1,000
Underwritten Public Offering \| Common Stock
Related Party Transaction [Line Items]
Issuance of stock shares (in shares)		5,577,500
Director \| Financial Advisory Services
Related Party Transaction [Line Items]
Expenses from transactions with related parties	$ 516,000
Expenses from transactions with related parties, net of related expenses	$ 500,000
Director \| Underwriting Fees
Related Party Transaction [Line Items]
Expenses from transactions with related parties			$ 944,000	$ 590,000
Expenses from transactions with related parties, net of related expenses			$ 849,000	$ 515,000
Director \| Underwriting Fees \| Common Stock
Related Party Transaction [Line Items]
Expenses from transactions with related parties		$ 1,000,000
Expenses from transactions with related parties, net of related expenses		$ 846,000