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Long-Term Debt (Tables) | 12 Months Ended
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Dec. 31, 2011
Long-Term Debt [Abstract] |
Long-term debt |
|  | December 31, 2011 |  |  | December 31, 2010 |
|  | (In thousands) |
$300 million floating rate revolving credit facility, due August 2016 |  | $ | — |  |  | $ | 94,000 |
5.55% senior notes, with semi-annual interest payments in June and December, maturing June 2013 |  |  | 35,000 |  |  |  | 35,000 |
4.91% senior notes, with semi-annual interest payments in June and December, with annual principal payments in June, maturing in June 2018 |  |  | 32,317 |  |  |  | 37,650 |
8.38% senior notes, with semi-annual interest payments in March and September, with scheduled principal payments beginning March 2013, maturing in March 2019 |  |  | 150,000 |  |  |  | 150,000 |
5.05% senior notes, with semi-annual interest payments in January and July, with annual principal payments in July, maturing in July 2020 |  |  | 69,230 |  |  |  | 76,923 |
5.31% utility local improvement obligation, with annual principal and interest payments, maturing in March 2021 |  |  | 1,922 |  |  |  | 2,115 |
5.55% senior notes, with semi-annual interest payments in June and December, with annual principal payments in June, maturing in June 2023 |  |  | 33,600 |  |  |  | 36,900 |
4.73% senior notes, with semi-annual interest payments in June and December, with scheduled principal payments beginning December 2014, maturing in December 2023 |  |  | 75,000 |  |  |  | — |
5.82% senior notes, with semi-annual interest payments in March and September, with annual principal payments in March, maturing in March 2024 |  |  | 195,000 |  |  |  | 210,000 |
8.92% senior notes, with semi-annual interest payments in March and September, with scheduled principal payments beginning March 2014, maturing in March 2024 |  |  | 50,000 |  |  |  | 50,000 |
5.03% senior notes, with semi-annual interest payments in June and December, with scheduled principal payments beginning December 2014, maturing in December 2026 |  |  | 175,000 |  |  |  | — |
5.18% senior notes, with semi-annual interest payments in June and December, with scheduled principal payments beginning December 2014, maturing in December 2026 |  |  | 50,000 |  |  |  | — |
Total debt |  |  | 867,069 |  |  |  | 692,588 |
Less — current portion of long term debt |  |  | (30,801 | ) |  |  | (31,518 | )
Long-term debt |  | $ | 836,268 |  |  | $ | 661,070 |
Principal payments due |
|  | Senior Notes |  |  | Credit Facility |  |  | Total |
|  | (In thousands) |
2012 |  | $ | 30,801 |  |  | $ | — |  |  | $ | 30,801 |
2013 |  |  | 87,230 |  |  |  | — |  |  |  | 87,230 |
2014 |  |  | 80,983 |  |  |  | — |  |  |  | 80,983 |
2015 |  |  | 80,983 |  |  |  | — |  |  |  | 80,983 |
2016 |  |  | 80,983 |  |  |  | — |  |  |  | 80,983 |
Thereafter |  |  | 506,089 |  |  |  | — |  |  |  | 506,089 |
|  | $ | 867,069 |  |  | $ | — |  |  | $ | 867,069 |
Summary of the four tranches of senior notes |
Series |  | Amount |  |  | Interest Rate |  |  | Issue Date |  |  | Maturity |
H |  |  | $75 million |  |  |  | 4.73 | % |  |  | April 20, 2011 |  |  |  | December 1, 2023 |
I |  |  | $125 million |  |  |  | 5.03 | % |  |  | April 20, 2011 |  |  |  | December 1, 2026 |
J |  |  | $50 million |  |  |  | 5.03 | % |  |  | June 15, 2011 |  |  |  | December 1, 2026 |
K |  |  | $50 million |  |  |  | 5.18 | % |  |  | October 3, 2011 |  |  |  | December 1, 2026 |

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- Definition Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21538-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(e),(f)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399 Reference 6: 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=6584090&loc=d3e28878-108400 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644 Reference 9: 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 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644 + Details
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