v3.8.0.1

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Statements of Cash Flows (Detail) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2017 | Sep. 30, 2016
Condensed Cash Flow Statements, Captions [Line Items] |  |
Net cash (used in) provided by operating activities | $ (1,868) | $ (7,148)
Investing activities: |  |
Purchase of property and equipment | (49,227) | (74,950)
Proceeds from asset dispositions | 21 | 13,233
Purchase of short-term investments | (268,525) | (263,204)
Proceeds from sale of short-term investments | 354,250 | 259,322
Payments of deposits on aircraft | 0 | (197)
Loan to unconsolidated affiliate | 0 | (1,200)
Net cash provided by (used in) investing activities | 36,519 | (66,996)
Financing activities: |  |
Proceeds from line of credit | 99,150 | 213,900
Payments on line of credit | (133,150) | (139,000)
Repurchase of common stock | (256) | (524)
Net cash (used in) provided by financing activities | (34,256) | 74,376
Increase (decrease) in cash | 395 | 232
Cash, beginning of period | 2,596 | 2,407
Cash, end of period | 2,991 | 2,639
Parent Company Only (issuer) [Member] |  |
Condensed Cash Flow Statements, Captions [Line Items] |  |
Net cash (used in) provided by operating activities | (43,328) | (32,467)
Investing activities: |  |
Purchase of property and equipment | (49,227) | (74,647)
Proceeds from asset dispositions | 21 | 13,233
Purchase of short-term investments | (268,525) | (263,204)
Proceeds from sale of short-term investments | 354,250 | 259,322
Payments of deposits on aircraft |  | (197)
Loan to unconsolidated affiliate |  | (1,200)
Net cash provided by (used in) investing activities | 36,519 | (66,693)
Financing activities: |  |
Proceeds from line of credit | 99,150 | 213,900
Payments on line of credit | (133,150) | (139,000)
Repurchase of common stock | (256) | (524)
Due to/from affiliate, net | 41,079 | 24,774
Net cash (used in) provided by financing activities | 6,823 | 99,150
Increase (decrease) in cash | 14 | (10)
Cash, beginning of period | 36 | 46
Cash, end of period | 50 | 36
Guarantor Subsidiaries [Member] |  |
Condensed Cash Flow Statements, Captions [Line Items] |  |
Net cash (used in) provided by operating activities | 33,670 | 25,319
Investing activities: |  |
Purchase of property and equipment | 0 | (303)
Net cash provided by (used in) investing activities | 0 | (303)
Financing activities: |  |
Due to/from affiliate, net | (34,699) | (24,774)
Net cash (used in) provided by financing activities | (34,699) | (24,774)
Increase (decrease) in cash | (1,029) | 242
Cash, beginning of period | 2,100 | 2,361
Cash, end of period | 1,071 | $ 2,603
Non-Guarantor Subsidiaries [Member] |  |
Condensed Cash Flow Statements, Captions [Line Items] |  |
Net cash (used in) provided by operating activities | 7,790 |
Investing activities: |  |
Net cash provided by (used in) investing activities | 0 |
Financing activities: |  |
Due to/from affiliate, net | (6,380) |
Net cash (used in) provided by financing activities | (6,380) |
Increase (decrease) in cash | 1,410 |
Cash, beginning of period | 460 |
Cash, end of period | $ 1,870 |

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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation. + 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 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 230 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=98513438&loc=d3e33268-110906 + Details
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- Definition Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 26 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3574-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585 + Details
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- Definition Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 26 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3574-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585 + Details
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- Definition Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585 + Details
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