Debt Covenant, Asset Proceeds, Excess Proceeds

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- Definition

Debt Covenant, Indenture Agreement, Period After Notice

+ References

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- Definition

Debt Instrument, Notice Period Prior to Redemption

+ References

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- Definition

Debt Instrument, Redemption Period, Change in Control, Percentage of Principal Amount Redeemable

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- Definition

Debt Instrument, Redemption Period, Percentage of Principal Amount Redeemable

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- Definition

Debt Instrument, Redemption Price Calculation Contributor, Percentage

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- Definition

Debt Instrument, Redemption Price, Percentage of Principal Remaining After Redemption

+ References

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- Definition

Redemption Period After Closing of Offering

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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.

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

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
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-SubTopic 470
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
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- 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

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-Name Accounting Standards Codification
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-Section S99
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Debt (5.125% Senior Notes) (Details) - USD ($)		12 Months Ended
Debt (5.125% Senior Notes) (Details) - USD ($)	Apr. 03, 2013	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Mar. 19, 2013
Debt Instrument [Line Items]
Capitalized loan costs		$ 48,900,000	$ 50,500,000
Loss on extinguishment of debt		$ 15,885,000	$ 0	$ 0
Senior Notes \| 5.125% Senior Notes
Debt Instrument [Line Items]
Debt instrument, face amount					$ 300,000,000.0
Stated interest rate		5.125%	5.125%		5.125%
Debt covenant, asset proceeds, excess proceeds		$ 25,000,000
Debt covenant, indenture agreement, period after notice		60 days
Percentage of principal amount redeemable		101.00%
Redemption period, principal amount redeemable		35.00%
Capitalized loan costs		$ 6,800,000
Redemption period after closing of offering		90 days
Redemption price percentage		105.125%
Percentage of principal remaining after redemption		65.00%
Redemption price calculation contributor, percentage		100.00%
Senior Notes \| 5.125% Senior Notes \| Redemption, Period 2018
Debt Instrument [Line Items]
Redemption price percentage		102.563%
Senior Notes \| 5.125% Senior Notes \| Redemption, Period 2019
Debt Instrument [Line Items]
Redemption price percentage		101.708%
Senior Notes \| 5.125% Senior Notes \| Redemption, Period 2020
Debt Instrument [Line Items]
Redemption price percentage		100.854%
Senior Notes \| 5.125% Senior Notes \| 2020 and thereafter
Debt Instrument [Line Items]
Redemption price percentage		100.00%
Senior Notes \| 5.125% Senior Notes \| Minimum
Debt Instrument [Line Items]
Notice period prior to redemption		30 days
Senior Notes \| 5.125% Senior Notes \| Maximum
Debt Instrument [Line Items]
Notice period prior to redemption		60 days
Senior Notes \| Credit Facility
Debt Instrument [Line Items]
Loss on extinguishment of debt	$ 4,400,000
Senior Notes \| Credit Agreement
Debt Instrument [Line Items]
Debt issuance cost	$ 1,100,000