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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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Note 16 - 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, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Amended and Restated Radian Group Inc. Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Stock Purchase Plan (ESPP), Shares in ESPP		1,250,000		1,250,000
Shares sold to employees under ESPP Plans				103,668
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		2.43%	1.76%
Volatility		32.80%	31.49%
Dividend yield		0.06%	0.05%
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	151,121
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	51,187
Employee Stock Purchase Plan (ESPP), Number of Shares Available for Issuance	1,997,613