Represents the incremental compensation expense resulting from modifications of the Company's compensation structure

No definition available.

Name:	den_IncrementalCompensationExpense
Namespace Prefix:	den_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of eligible individuals

+ References

No definition available.

+ Details

Name:	den_NumberOfEligibleIndividuals
Namespace Prefix:	den_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Repayment Percentage

+ References

No definition available.

+ Details

Name:	den_RepaymentPercentage
Namespace Prefix:	den_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Compensation expense not yet recognized

+ References

No definition available.

+ Details

Name:	den_UnrecognizedCompensationExpense
Namespace Prefix:	den_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of reorganization items related to employee related charges.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56145-112766

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=116635682&loc=d3e55730-112764

+ Details

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

- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Payments of cash to employees, including wages and salaries, during the current period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585

+ Details

Name:	us-gaap_PaymentsToEmployees
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

+ Details

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

- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

+ References

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 3: 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(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: 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(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_RangeAxis=den_ContinuedEmploymentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=den_SpecifiedIncentiveMetricMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_PhantomShareUnitsPSUsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_StockAppreciationRightsSARSMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_PerformanceSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=den_A2020OmnibusStockAndIncentivePlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=den_A2004OmnibusStockAndIncentivePlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Stock Compensation (Details Textual)	1 Months Ended		3 Months Ended		9 Months Ended	12 Months Ended
Stock Compensation (Details Textual)	Dec. 31, 2020 USD ($) shares	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) shares	Sep. 18, 2020 USD ($) shares	Sep. 18, 2020 USD ($) shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 shares	Dec. 31, 2018 USD ($) shares
Stock Compensation Plans (Textuals)
Total executives and senior managers receiving cash retention incentive		21
Total cash retention incentives paid to executive officers and senior managers \| $		$ 15,200,000
Repayment percentage		100.00%
Unrecognized compensation expense \| $		$ 18,700,000
Incremental compensation expense \| $		$ 4,100,000
Acceleration of Predecessor stock compensation expense \| $				$ 4,600,000	$ 4,601,000
Number of awards exercised \| shares					0
Percentage based on continued employment
Stock Compensation Plans (Textuals)
Repayment percentage		50.00%
Percentage based on metrics
Stock Compensation Plans (Textuals)
Repayment percentage		50.00%
Restricted Stock Units
Stock Compensation Plans (Textuals)
Total grants \| shares			1,219,867
Total compensation cost to be recognized in future periods \| $	$ 29,300,000		$ 29,300,000			$ 29,300,000
Weighted average period over which remaining cost will be recognized			2 years 10 months 24 days
Performance Share Units
Stock Compensation Plans (Textuals)
Total grants \| shares			1,021,222
Award vesting or performance period			3 years
Total compensation cost to be recognized in future periods \| $	$ 16,600,000		$ 16,600,000			$ 16,600,000
Weighted average period over which remaining cost will be recognized			2 months 12 days
Stock Appreciation Rights (SARs)
Stock Compensation Plans (Textuals)
Award vesting or performance period					3 years
Total compensation cost to be recognized in future periods \| $								$ 0
SARs expiration period					7 years
Grant-date fair value of SARs vested \| $								$ 1,100,000
Number of awards exercised \| shares					0		0	0
Restricted Stock
Stock Compensation Plans (Textuals)
Total grants \| shares					0
Award vesting or performance period					3 years	3 years
Total compensation cost to be recognized in future periods \| $				$ 0	$ 0
Performance-based equity awards
Stock Compensation Plans (Textuals)
Award vesting or performance period					3 years 3 months
Payout percentage					59.00%
Performance-based equity awards \| Minimum
Stock Compensation Plans (Textuals)
Award vesting or performance period						1 year 3 months
Payout percentage					0.00%
Performance-based equity awards \| Maximum
Stock Compensation Plans (Textuals)
Payout percentage					200.00%
2020 Omnibus Stock and Incentive Plan
Stock Compensation Plans (Textuals)
Maximum number of common stock shares authorized for issuance under Plan \| shares	6,200,000		6,200,000			6,200,000
Total grants \| shares	2,200,000
Shares available for future awards \| shares	4,000,000.0		4,000,000.0			4,000,000.0
2004 Omnibus Stock and Incentive Plan
Stock Compensation Plans (Textuals)
Maximum number of common stock shares authorized for issuance under Plan \| shares				61,400,000	61,400,000