Derivative Instruments, Effective Portion Of Accumulated Loss at Discontinuance, Before Tax

No definition available.

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- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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- Definition

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

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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- Definition

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

+ References

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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

Amount of advances from the Federal Home Loan Bank (FHLB).

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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- Definition

Amount of interest expense classified as other.

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- Definition

The amount of cash paid for interest during the period.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

The loss recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

No definition available.

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Debt (Details) - USD ($)			12 Months Ended
Debt (Details) - USD ($)	Jun. 12, 2017	Feb. 24, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Feb. 27, 2014
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances			$ 0
Gains (Losses) on Extinguishment of Debt			0	$ 0	$ (9,100,000)
Loss on Cash Flow Hedge Ineffectiveness			1,100,000
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months			(400,000)
Cash Flow Hedge Derivative Instrument Assets at Fair Value				1,600,000
Interest Expense			34,900,000	44,400,000	46,500,000
Interest Paid			34,700,000	44,200,000	$ 44,100,000
Notes Payable under Revolving Credit Agreement
Debt Instrument [Line Items]
Line of credit, outstanding			0	0
Subordinated Debt [Member] \| Subordinated Debenture, 7.375 Percent Due 2054 [Member]
Debt Instrument [Line Items]
Stated interest rate, percentage						7.375%
Senior Notes [Member] \| Senior Notes, 4.35 Percent Due February 15, 2025 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 200,000,000	$ 250,000,000.0	450,000,000
Stated interest rate, percentage		4.35%
Issuance costs	$ 200,200,000	$ 247,300,000
Interest rate, effective percentage	4.16%	4.49%
Senior Notes [Member] \| Senior Notes, 6% Due November 30, 2015 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 250,000,000
Stated interest rate, percentage		6.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			225,000,000
Federal Home Loan Bank of Chicago [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances			0	0
Federal Home Loan Bank of Dallas [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances			0	$ 0
Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Debt Instrument [Line Items]
Derivative Instruments, Effective Portion Of Accumulated Loss at Discontinuance, Before Tax			4,500,000
Interest Expense, Other			$ 200,000