v3.6.0.2

Long Term Debt (Tables) | 12 Months Ended
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Dec. 31, 2016
Debt Disclosure [Abstract] |
Components of Long-term Debt | The components of long-term debt as of December 31 are as follows:
|  | December 31, 2016 |  |  | December 31, 2015 |
|  |  |  |  | Unamortized |  |  |  |  |  | Unamortized |
|  |  |  |  | Debt |  |  |  |  |  | Debt |
|  |  |  |  | Issuance |  |  |  |  |  | Issuance |
|  | Principal |  |  | Debt Cost |  |  | Principal |  |  | Debt Cost |
|  | (Thousands of dollars) |
Senior Notes issued March 17, 2014, interest only payable semi-annually at 5.25%, maturing March 15, 2019 |  | $ | 500,000 |  |  | $ | 2,753 |  |  | $ | 500,000 |  |  | $ | 3,999 |
Revolving Credit Facility due October 1, 2018 with a group of commercial banks, interest payable at variable rates |  |  | 134,000 |  |  |  | — |  |  |  | 57,500 |  |  |  | — |
Total long-term debt |  | $ | 634,000 |  |  | $ | 2,753 |  |  | $ | 557,500 |  |  | $ | 3,999 |
Summary of Annual Maturities of Long-term Debt | Listed below is information on our future annual maturities of long-term debt (in thousands):
2017 |  | $ | — |
2018 |  |  | 134,000 |
2019 |  |  | 500,000 |
2020 |  |  | — |
2021 |  |  | — |
Thereafter |  |  | — |
Total |  | $ | 634,000 |

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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 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 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 3: 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 4: 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=26873400&loc=d3e23780-122690 Reference 5: 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 Reference 6: 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 7: 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 Reference 8: 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=64930785&loc=d3e28541-108399 Reference 9: 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=64930785&loc=d3e28551-108399 Reference 10: 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 + Details
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- Definition Tabular disclosure of the combined aggregate amount of maturities and sinking fund requirements for all long-term borrowings for each of the five years following the date of the latest balance sheet date presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 + Details
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