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Long-Term Debt - Outstanding Long-Term Debt (Phantoms) (Detail) | 12 Months Ended
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Dec. 31, 2018
9.08% bond, due June 1, 2022 |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 9.08%
Debt Instrument, Maturity Date | Jun. 01, 2022
6.64% note, due October 31, 2017 |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 6.64%
Debt Instrument, Maturity Date | Oct. 31, 2017
5.50% note, due October 12, 2020 |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 5.50%
Debt Instrument, Maturity Date | Oct. 12, 2020
5.93% note, due October 31, 2023 |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 5.93%
Debt Instrument, Maturity Date | Oct. 31, 2023
5.68% note, due June 30, 2026 |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 5.68%
Debt Instrument, Maturity Date | Jun. 30, 2026
6.43% note, due May 2, 2028 |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 6.43%
Debt Instrument, Maturity Date | May 02, 2028
3.73% note, due December 16, 2028 |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 3.73%
Debt Instrument, Maturity Date | Dec. 16, 2028
3.88% note, due May 15, 2029 |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 3.88%
Debt Instrument, Maturity Date | May 15, 2029
Uncollateralized Senior Note Due on Two Thousand Thirty Two [Member] |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 3.25%
Debt Instrument, Maturity Date | Apr. 30, 2032
Uncollateralized Senior Note Due May Two Thousand Thirty Eight [Member] |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 3.48%
Debt Instrument, Maturity Date | May 31, 2038
Uncollateralized Senior Note Due November Two Thousand Thirty Eight [Member] |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 3.58%
Debt Instrument, Maturity Date | Nov. 30, 2038
Term Note Due January Two Thousand Twenty [Member] |
Debt Instrument [Line Items] |
Long-term debt, interest percentage | 3.23%
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate | 0.75%
Debt Instrument, Maturity Date | Jan. 21, 2020

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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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. + Details
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- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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