$ 1,750,000

1,738,321

$ 1,740,985

Debt Instrument, Unamortized Discount (Premium), Net

(5,413)

(2,668)

2.7% Senior Notes [Member]

19,760

250,000

253,985

256,055

Debt Instrument, Unamortized Discount

(5,413)

332

3.95% Senior Notes [Member]

1,096

250,000

248,088

248,028

Debt Instrument, Unamortized Discount

366

4.75% Senior Notes [Member]

1,546

450,000

446,546

447,030

Debt Instrument, Unamortized Premium

5.625% Senior Notes [Member]

3,454

550,000

547,801

547,781

Debt Instrument, Unamortized Premium

(3,366)

6.375% Junior Notes [Member]

5,565

250,000

241,901

$ 242,091

Debt Instrument, Unamortized Premium

$ 8,099

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.

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
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-Subparagraph (SX 210.7-03(16))
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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.

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Amount, after accumulated amortization, of debt discount.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt premium.

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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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.

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