Long-Term Debt (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Debt Instrument [Line Items]
Long-term Debt	$ 736.6
Maturity start date range	Jan. 01, 2019
Maturity end date range	Dec. 31, 2048
Weighted average interest rate	5.009%
Minimum [Member]
Debt Instrument [Line Items]
Stated interest rate	2.822%
Maximum [Member]
Debt Instrument [Line Items]
Stated interest rate	9.05%

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
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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
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-Subparagraph (b)(3)
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-Name Accounting Standards Codification
-Topic 942
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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

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