Termination of line of credit facility.

No definition available.

Name:	do_TerminationOfLineOfCreditFacility
Namespace Prefix:	do_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Includes any additional disclosures related to the credit quality of financing receivables. This may include a description of a credit quality indicator or a description of how the internal risk ratings used by a company relate to the likelihood of loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 29
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953659-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953664-111524

+ Details

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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

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

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

Reference 2: 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.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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

- Details

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- Details

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- Details

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Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Credit Agreements and Credit Ratings - Additional Information (Detail) - USD ($)			1 Months Ended	3 Months Ended
	Apr. 16, 2020	Mar. 17, 2020	Mar. 31, 2020	Mar. 31, 2020	Apr. 28, 2020	Apr. 26, 2020	Jan. 31, 2020
Debt Instrument [Line Items]
Line of credit facility, amount borrowed				$ 436,000,000
Subsequent Event [Member]
Debt Instrument [Line Items]
Line of credit issued						$ 436,000,000.0
Credit Ratings	On March 9, 2020, Moody’s Investor Services (“Moody’s), downgraded our current corporate credit rating to Caa1 from B2 and our current senior unsecured notes credit rating to Caa2 from B3. On April 16, 2020, Moody’s further downgraded both our corporate credit rating and our current senior unsecured notes credit rating to Ca. And, on April 27, 2020, Moody’s downgraded our corporate credit rating to D. The rating outlook from Moody’s is negative. Additionally, on April 16, 2020, S&P Global Ratings (“S&P”) downgraded our corporate and senior unsecured notes credit ratings to CC from CCC+ and our Credit Agreement rating to CC from B-. On April 24, 2020, S&P lowered our corporate credit rating and all issue-level credit ratings to D. Our rating outlook from S&P has been designated as not meaningful. Our current credit ratings are below investment grade and could raise our cost of financing. Consequently, we may not be able to issue additional debt in amounts and/or with terms that we consider to be reasonable. These ratings could limit our ability to pursue other business opportunities.
Amended Credit Agreement [Member] \| Credit facility Mature on October 22, 2020 [Member]
Debt Instrument [Line Items]
Termination of credit agreement		$ 225,000,000.0
Credit facility, scheduled maturity date		Oct. 22, 2020
Write-off of deferred arrangement fees		$ 500,000
950 Million Credit Agreement [Member]
Debt Instrument [Line Items]
Line of credit facility, amount borrowed			$ 436,000,000.0
Amount available for general purposes			$ 950,000,000.0	$ 950,000,000.0	$ 442,000,000.0
Credit facility, term			5 years
Weighted average interest rate on borrowings			5.32%	5.32%
Line of credit issued			$ 436,000,000.0	$ 436,000,000.0
950 Million Credit Agreement [Member] \| Financial Letter of Credit [Member]
Debt Instrument [Line Items]
Line of credit issued							$ 6,000,000.0