Dividends Restrictions (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Dividends Restrictions
Dividends paid to parent company	$ 0	$ 55,000,000.0	$ 0
Total equity	3,862,633,000	2,984,845,000	2,365,717,000
Essent Guaranty
Dividends Restrictions
Unassigned surplus	343,600,000
Dividends paid to parent company	0	0	40,000,000
Essent PA
Dividends Restrictions
Unassigned surplus	15,400,000
Dividends paid to parent company	0	$ 0	$ 0
Essent Re
Dividends Restrictions
Total equity	1,100,000,000
Essent Re \| Essent Guaranty \| Minimum \| Quota share reinsurance
Dividends Restrictions
Total equity	$ 100,000,000

This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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- Definition

Amount of statutory capital and surplus computed using prescribed or permitted statutory accounting practice.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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.

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

+ References

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-Publisher FASB
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-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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