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

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- Definition

Interest Rate to be added as Part of the Milestone payment

+ References

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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)

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- Definition

The current portion of money or property received from customers which is either to be returned upon satisfactory contract completion or applied to customer receivables in accordance with the terms of the contract or the understandings.

+ 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 210.5-02.20)

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

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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 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 15

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

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No definition available.

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- Definition

The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.

+ References

No definition available.

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

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Property and Equipment - Narrative (Details) (USD $)	3 Months Ended		6 Months Ended
Property and Equipment - Narrative (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Property, Plant and Equipment
Asset impairment	$ 0	$ 0	$ 60,777,000	$ 0
Proceeds from sale of assets			2,524,000	57,517,000
Other, net	0us-gaap_OtherOperatingIncomeExpenseNet	(1,602,000)us-gaap_OtherOperatingIncomeExpenseNet	0us-gaap_OtherOperatingIncomeExpenseNet	(1,602,000)us-gaap_OtherOperatingIncomeExpenseNet
(Gain) loss on sale of assets	5,529,000	(32,442,000)	15,335,000	(34,079,000)
Atwood Hunter
Property, Plant and Equipment
Asset impairment			60,800,000
Impairment, Net of Tax			56,100,000
Impairment Effect on Earnings Per Share, after Tax			$ 0.86
Equipment \| Atwood Hunter
Property, Plant and Equipment
Asset impairment			48,000,000
Inventory \| Atwood Hunter
Property, Plant and Equipment
Asset impairment			8,400,000
Atwood Hunter
Property, Plant and Equipment
Proceeds from sale of assets			2,900,000
Deposit from Sale of Atwood Hunter	1,800,000		1,800,000
(Gain) loss on sale of assets			5,500,000
Impairment, Net of Tax			5,500,000
Impairment Effect on Earnings Per Share, after Tax			$ 0.08
Atwood Southern Cross
Property, Plant and Equipment
Proceeds from sale of assets			2,100,000
Other, net			(2,000,000)
(Gain) loss on sale of assets			8,000,000
Impairment, Net of Tax			7,100,000
Impairment Effect on Earnings Per Share, after Tax			$ 0.11
Construction in Progress, Newbuild Drilling Units
Property, Plant and Equipment
Expenditure towards construction of drilling units currently under construction	432,000,000		432,000,000
Construction in Progress, Newbuild Drilling Units \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			704,000,000
Interest Rate Per Annum to be Added with the Milestone Payment	3.50%		3.50%
Atwood Admiral \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			321,000,000
Atwood Admiral \| Milestone Payment No 1 \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			50,000,000
Atwood Admiral \| Milestone Payment No 2 \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			25,000,000
Atwood Admiral \| Milestone Payment No 3 \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			150,000,000
Atwood Admiral \| Final Payment \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			146,000,000
Atwood Archer \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			383,000,000
Atwood Archer \| Milestone Payment No 1 \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			50,000,000
Atwood Archer \| Milestone Payment No 2 \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			25,000,000
Atwood Archer \| Final Payment \| Capital Addition Purchase Commitments
Property, Plant and Equipment
Commitments on drilling units under construction			$ 358,000,000