$ 2,250,000

2,221,896

$ 1,740,985

Debt Instrument, Unamortized Discount (Premium), Net

(4,962)

(2,676)

2.7% Senior Notes [Member]

35,742

250,000

253,650

256,055

Debt Instrument, Unamortized Discount

(4,962)

305

3.95% Senior Notes [Member]

1,007

250,000

248,147

248,028

Debt Instrument, Unamortized Discount

354

4.75% Senior Notes [Member]

1,499

450,000

446,635

447,030

5.45% Junior Subordinated Notes [Member]

3,365

500,000

483,691

5.625% Senior Notes [Member]

16,309

550,000

547,821

547,781

(3,335)

6.375% Junior Notes [Member]

5,514

250,000

241,952

$ 242,091

$ 8,048

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
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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
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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.

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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.

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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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