The discount from the market price on the date of purchase.

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- Definition

Employee Stock Purchase Plan (ESPP), Number of Shares Available for Issuance

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Employee Stock Purchase Plan (ESPP), Shares in ESPP

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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No definition available.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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Note 15 - Share-Based and Other Compensation Programs Employee Stock Purchase Plan (Details) - Employee Stock Purchase Plan - shares	1 Months Ended	6 Months Ended		12 Months Ended
	Jan. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amended and Restated Radian Group Inc. Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares sold to employees under ESPP Plans				107,009	103,668
Employee Stock Purchase Plan (ESPP), Shares in ESPP					1,250,000
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date				15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected life (months)		6 months	6 months	6 months
Risk-free interest rate		2.18%	2.76%
Volatility		27.90%	36.24%
Dividend yield		0.04%	0.06%
Employee Stock Purchase Plan 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares sold to employees under ESPP Plans						105,476
Subsequent Event \| Amended and Restated Radian Group Inc. Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares sold to employees under ESPP Plans	39,332
Employee Stock Purchase Plan (ESPP), Number of Shares Available for Issuance	1,902,459