Schedule of Balances with Unconsolidated Affiliates (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Due from related parties:
Total due from related parties	$ 125,972	$ 132,951
Total due from related parties	125,972	132,951
Due to related parties:
Total due to related parties	50,186	34,972
Due from related parties, net of due to related parties	75,786	97,979
Total due to related parties	50,186	34,972
Sonatide Marine, Ltd. \| ANGOLA
Due from related parties:
Total due from related parties	89,246	109,176
Total due from related parties	89,246	109,176
Due to related parties:
Total due to related parties	31,475	29,347
Total due to related parties	31,475	29,347
DTDW Holdings, Ltd. \| NIGERIA
Due from related parties:
Total due from related parties	36,726	23,775
Total due from related parties	36,726	23,775
Due to related parties:
Total due to related parties	18,711	5,625
Total due to related parties	$ 18,711	$ 5,625

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: 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(11))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: 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(3)(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant