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Long-Term Debt and Long-Term Debt Payable to Related Parties - Carrying Amounts and Estimated Fair Values of Senior Notes (Parenthetical) (Detail) | 3 Months Ended
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Mar. 31, 2018
2019 Promissory Notes [Member] |
Debt Instrument [Line Items] |
Maturity date | Dec. 09, 2019
2042 Promissory Notes [Member] |
Debt Instrument [Line Items] |
Maturity date | Jun. 26, 2042

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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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Period Type: | duration

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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/presentationRef -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 + Details
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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |