Income Taxes - Schedule of Reconciliation of Income Tax Expense (Benefit) Computed by Applying Statutory Federal Income Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amount
Computed expected federal income tax	$ 189,047	$ 146,609	$ (79,952)
State income tax, net of federal income tax benefit	14,773	11,850	(4,239)
Deferred tax adjustment related to change in overall state tax rate	(660)	(15,208)	(48)
Valuation allowance	17,676	8,975	(505)
Provision to return adjustments	(1,966)	(1,773)	(3,242)
Excess stock compensation	(918)	327	2,965
Tax Act	0	(11,367)	(242,875)
Other, net	1,202	1,681	(932)
Income tax expense (benefit)	$ 219,154	$ 141,094	$ (328,828)
Rate
Computed expected federal income tax	21.00%	21.00%	35.00%
State income tax, net of federal income tax benefit	1.64%	1.70%	1.86%
Deferred tax adjustment related to change in overall state tax rate	(0.07%)	(2.18%)	0.02%
Valuation allowance	1.96%	1.29%	0.22%
Provision to return adjustments	(0.22%)	(0.25%)	1.42%
Excess stock compensation	(0.10%)	0.05%	(1.30%)
Tax Act	0	(0.0163)	1.0632
Other, net	0.13%	0.24%	0.41%
Income tax expense (benefit)	24.34%	20.21%	143.95%

Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, State and Local, Percent

No definition available.

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Namespace Prefix:	cog_
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

The portion of the difference, between total income tax expense or benefit as reported in the income statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to deferred tax adjustment related to change in overall state tax rate.

+ References

No definition available.