Accelerated Delivery Notice Period

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- Definition

Construction in Progress, Period Of Delivery Delay

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No definition available.

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- Definition

Impairment of Long-Lived Assets to be Disposed of, Net of Tax

+ References

No definition available.

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- Definition

Insurance Recoveries Effect on Earnings Per Share Diluted, after Tax

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No definition available.

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- Definition

Insurance Recoveries, Net of Tax

+ References

No definition available.

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- Definition

Number Of Drillships With Options To Delay Delivery

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No definition available.

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- Definition

Payment for Construction in Process, Future Payment, Amount

+ References

No definition available.

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

After tax earnings per share or per unit impact arising from asset impairment.

+ References

No definition available.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2611-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

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- Definition

The cash outflow from construction costs to date on capital projects that have not been completed and assets being constructed that are not ready to be placed into service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

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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.

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PROPERTY AND EQUIPMENT - Narrative (Details) $ / shares in Units, $ in Thousands				3 Months Ended			12 Months Ended
	Dec. 13, 2016 USD ($)	Dec. 05, 2016 drillship	Dec. 17, 2015 USD ($)	Dec. 31, 2016 USD ($) drillship	Sep. 30, 2016 USD ($)	Dec. 31, 2015 USD ($) $ / shares	Sep. 30, 2016 USD ($) $ / shares
Property, Plant and Equipment
Asset impairment				$ 0		$ 64,724
Construction in Progress, Ultra-Deepwater Drillships \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Construction in progress, gross				$ 970,000
Number of drillships with options to delay delivery \| drillship				2
Wells and Related Equipment and Facilities
Property, Plant and Equipment
Commitments on drilling units under construction					$ 300,000
Atwood Falcon
Property, Plant and Equipment
Asset impairment						64,700
Impairment, net of tax						$ 64,700
Impairment effect on earnings per share, after tax (in dollars per share) \| $ / shares						$ 1.00
Atwood Falcon \| Equipment
Property, Plant and Equipment
Asset impairment						$ 53,000
Atwood Falcon \| Inventory
Property, Plant and Equipment
Asset impairment						$ 11,700
Atwood Osprey
Property, Plant and Equipment
Insurance recoveries							$ 18,000
Insurance recoveries, net of tax							$ 18,000
Insurance recoveries effect on earnings per share, after tax (in dollars per share) \| $ / shares							$ 0.28
Atwood Admiral and Atwood Archer \| Ultra-Deepwater Drillships \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Construction in progress, period of delivery delay		2 years
Number of drillships with options to delay delivery \| drillship		2
Atwood Admiral
Property, Plant and Equipment
Accelerated delivery notice period (in days)				45 days
Atwood Admiral \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Payment for construction in process, future payment, amount				$ 10,000
Atwood Admiral \| Capital Addition Purchase Commitments \| Final Payment
Property, Plant and Equipment
Commitments on drilling units under construction			$ 83,900
Atwood Archer \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Payments for construction projects	$ 125,000
Payment for construction in process, future payment, amount				15,000
Atwood Archer \| Capital Addition Purchase Commitments \| Final Payment
Property, Plant and Equipment
Commitments on drilling units under construction				$ 165,000
Promissory Note \| Ultra-Deepwater Drillships
Property, Plant and Equipment
Stated interest rate				5.00%