Commitments and Contingencies - Schedule of Contractual Obligations, Commitments and Contingencies (Detail) $ in Thousands	Dec. 31, 2018 USD ($)
Long-Term Debt [Member]
Commitment And Contingencies [Line Items]
Payments due in 1 year	$ 292
Payments due in 2 years	335
Payments due in 3 years	359
Payments due in 4 years	383
Payments due in 5+ years	1,946
Contractual obligations, commitments and contingencies	3,315
Operating Leases [Member]
Commitment And Contingencies [Line Items]
Payments due in 1 year	558
Payments due in 2 years	383
Payments due in 3 years	197
Payments due in 4 years	27
Payments due in 5+ years	3
Contractual obligations, commitments and contingencies	1,168
Interest on Outstanding Debt [Member]
Commitment And Contingencies [Line Items]
Payments due in 1 year	193
Payments due in 2 years	190
Payments due in 3 years	167
Payments due in 4 years	142
Payments due in 5+ years	309
Contractual obligations, commitments and contingencies	$ 1,001

Commitment And Contingencies [Line Items]

No definition available.

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- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation maturing in the remainder of the fiscal year following the latest fiscal year ended.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Period Type:

- Details

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- Details

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