Number of allowable extensions under Credit Agreement and term of extension.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Debt To Equity Ratio

+ References

No definition available.

+ Details

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

- Definition

Line of credit facility additional capacity available.

+ References

No definition available.

+ Details

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

- Definition

Fees paid to lender for issuance of letters of credit, calculated as a percentage of the face amount of the letter of credit.

+ References

No definition available.

+ Details

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Namespace Prefix:	do_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

+ Details

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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.

+ Details

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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

+ 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

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

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Data Type:	xbrli:stringItemType
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 borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ 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(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

Weighted average interest rate of short-term debt outstanding.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Credit Agreement, Commercial Paper and Senior Notes - Credit Agreement - Additional Information (Detail) - USD ($)		12 Months Ended
	Oct. 22, 2015	Dec. 31, 2016	Feb. 10, 2017	Dec. 31, 2015
Debt Instrument [Line Items]
Commitment fee on unused commitments		0.20%
Participation fees for letters of credit		0.625%
Ratio of consolidated indebtedness to total capitalization		60.00%
Amount outstanding under credit agreement				$ 0
Borrowings outstanding		$ 104,200,000		$ 286,589,000
Borrowings weighted average interest rate		1.90%
Subsequent Event [Member]
Debt Instrument [Line Items]
Amount outstanding under credit agreement			$ 0
Additional amount available under Credit Agreement			$ 1,500,000,000
Eurodollar [Member]
Debt Instrument [Line Items]
Basis point increase		1.00%
Federal Funds Rate [Member]
Debt Instrument [Line Items]
Basis point increase		0.50%
ABR Loans [Member]
Debt Instrument [Line Items]
Interest margin		0.25%
Eurodollar Loans [Member]
Debt Instrument [Line Items]
Interest margin		1.25%
Minimum [Member]
Debt Instrument [Line Items]
Commitment fee on unused commitments		0.06%
Maximum [Member]
Debt Instrument [Line Items]
Commitment fee on unused commitments		0.20%
Swingline Loans [Member]
Debt Instrument [Line Items]
Amount available for general purposes	$ 100,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Amount available for general purposes	$ 1,500,000,000
Maturity period of credit agreement	Oct. 22, 2020
Additional amount available under revolving credit facility	$ 500,000,000
Extension of the maturity date under credit agreement		One additional one-year extension of the maturity date
Credit Agreement Commitments Mature on March 17, 2019 [Member]
Debt Instrument [Line Items]
Amount available for general purposes	$ 40,000,000
Maturity period of credit agreement	Mar. 17, 2019
Credit Agreement Commitments Mature on October 22, 2019 [Member]
Debt Instrument [Line Items]
Amount available for general purposes	$ 60,000,000
Maturity period of credit agreement	Oct. 22, 2019
Letters of Credit [Member]
Debt Instrument [Line Items]
Amount available for general purposes	$ 250,000,000
Swingline Loan Facility [Member]
Debt Instrument [Line Items]
Swingline loans bear interest description		Swingline loans bear interest, at our option, at a rate per annum equal to (i) the ABR plus the applicable interest margin for ABR loans or (ii) the daily one-month Eurodollar Rate plus the applicable interest margin for Eurodollar loans
Performance Letters of Credit [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Participation fees for letters of credit		0.375%
Performance Letters of Credit [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Participation fees for letters of credit		0.625%
Other Letter of Credit [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Participation fees for letters of credit		0.75%
Other Letter of Credit [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Participation fees for letters of credit		1.25%