Comprehensive Loss - Summary of Amounts Reclassified out of Accumulated Other Comprehensive Loss (Detail) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balances	$ 82,756,000	$ 151,068,000
Amounts reclassified out of other comprehensive loss		350,000
Net current period other comprehensive loss	0	350,000
Ending Balances	$ 59,945,000	82,756,000
Unrealized Gains and Losses on Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balances		(350,000)
Amounts reclassified out of other comprehensive loss		350,000
Net current period other comprehensive loss		350,000
Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balances		$ (350,000)

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.

No definition available.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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