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

Amount of other outstanding indebtedness that the entity may default on, triggering a cross default on indebtedness under the credit facility.

No definition available.

Name:	do_AmountOfOtherOutstandingIndebtednessForCrossDefaultTrigger
Namespace Prefix:	do_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Equity interest pledged as collateral.

No definition available.

Name:	do_EquityInterestPledgedAsCollateral
Namespace Prefix:	do_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Percentage of consolidated indebtedness to capitalization.

No definition available.

Name:	do_PercentageOfConsolidatedIndebtednessToCapitalization
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Data Type:	num:percentItemType
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Period Type:	duration

Ratio of the carrying value of marketed rigs to total commitments, as defined in credit agreement.

No definition available.

Name:	do_RatioOfValueOfMarketedRigsToCommitments
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Data Type:	xbrli:pureItemType
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Period Type:	duration

Minimum ratio of the value of rigs owned by the borrowers and guarantors to total carrying value of all rigs owned by the company.

No definition available.

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Period Type:	duration

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.

No definition available.

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Period Type:	duration

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.

No definition available.

Name:	us-gaap_DebtInstrumentTerm
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Data Type:	xbrli:durationItemType
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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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
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-Section S99
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

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.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
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Namespace Prefix:
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Name:	us-gaap_DebtInstrumentAxis=do_CreditFacilityMatureOnOctoberTwentyTwoTwoThousandTwentyMember
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Data Type:	na
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