Line of Credit Facility, Additional Borrowing Capacity, Available

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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

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

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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

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	debit
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Debt - Debt Outstanding (Details) - USD ($)			12 Months Ended
Debt - Debt Outstanding (Details) - USD ($)	Jun. 12, 2017	Feb. 24, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jul. 02, 2018	Jun. 30, 2018	Jun. 29, 2018	Jun. 08, 2018
Debt Instrument [Line Items]
Repayments of Debt			$ 215,000,000	$ 360,000,000	$ 0
Long-term Debt, Current and Non-current, at Amortized Cost (Fair Value: 2018 - $911.2; 2017 - $614.6)			909,000,000	592,300,000
Senior Notes [Member] \| Term Loan Due 2020 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount								$ 250,000,000.0
Long-term Debt, Gross			34,900,000	0
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
Long-term Debt, Gross			448,400,000	448,100,000
Long-term Debt, Current and Non-current, at Amortized Cost (Fair Value: 2018 - $911.2; 2017 - $614.6)			450,000,000
Issuance costs	$ 200,200,000	$ 247,300,000
Senior Notes [Member] \| Senior Note Due on September Nineteen,Twenty Twenty Two [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			281,500,000	0
Subordinated Debt [Member] \| Subordinated Debenture, 7.375 Percent Due 2054 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			144,200,000	144,200,000
Federal Home Loan Bank of Chicago [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances			10,000,000	0			$ 55,000,000
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			$ 55,000,000
Revolving Credit Facility [Member] \| Credit facility and Secured Loan [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Additional Borrowing Capacity, Available									$ 100,000,000
Infinity [Member] \| Senior Notes [Member] \| Senior Note Due on September Nineteen,Twenty Twenty Two [Member]
Debt Instrument [Line Items]
Debt instrument, face amount						$ 275,000,000