Subsidiaries, Ownership Percentage

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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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.

+ Details

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Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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Long-Term Debt 6.000% Senior Notes due 2026 (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Mar. 28, 2016
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 3,563,931	$ 3,121,558
Unamortized Debt Issuance Expense	50,909	44,122
Parent
Debt Instrument [Line Items]
Long-term Debt, Gross	3,563,931	3,121,558
Subsidiaries, Ownership Percentage			100.00%
Unamortized Debt Issuance Expense	$ 50,909	$ 44,122
Parent \| Senior Notes [Member] \| 6.000% Senior Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.00%
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed	101.00%
Subsidiaries, Ownership Percentage	100.00%
Unamortized Debt Issuance Expense	$ 11,027
Parent \| Senior Notes [Member] \| 6.000% Senior Notes Due 2026 [Member] \| Base Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Increase (Decrease)	0.25%
Parent \| Senior Notes [Member] \| 6.000% Senior Notes Due 2026 [Member] \| Base Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Increase (Decrease)	1.00%
Fair Value, Measurements, Nonrecurring [Member] \| Parent \| Senior Notes [Member] \| 6.000% Senior Notes Due 2026 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 700,000
After August 15, 2021 and Prior to 2024 [Domain] \| Parent \| Senior Notes [Member] \| 6.000% Senior Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	103.00%
Prior to August 15, 2024 [Domain] \| Parent \| Senior Notes [Member] \| 6.000% Senior Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100.00%