Basis of Presentation and Business Overview

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Business Overview [Abstract]

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Mortgage Insurance [Abstract]

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Percentage Of Primary Insurance On Domestic First-Lien Mortgages To Total Risk In Force

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This element represents the maximum down payment percentage on a home's purchase price that is used to measure the need for private mortgage insurance.

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Risk In Force

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Amount of cash inflow (outflow) of investing activities of discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Face (par) amount of the original debt instrument that was repurchased.

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Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

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Increase (decrease) in cash associated with the entity's discontinued operations.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The cash outflow to reacquire common stock during the period.

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The cash outflow to acquire debt and equity securities not classified as either held-to-maturity securities or trading securities which would be classified as available-for-sale securities and reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity.

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The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Note 1 - Condensed Consolidated Financial Statements - Business Overview and Significant Accounting Policies Business Overview and Significant Accounting Policies(Details)	1 Months Ended	3 Months Ended			9 Months Ended
	Jun. 30, 2016 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) segment	Sep. 30, 2015 USD ($)	Aug. 12, 2016 USD ($)	Jun. 29, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Basis of Presentation and Business Overview [Line Items]
Net Cash Provided by (Used in) Investing Activities					$ (87,055,000)	$ 19,451,000
Proceeds from Sale and Maturity of Fixed-Maturity Investments Available-for-sale					537,679,000	16,208,000
Payments to Acquire Available-for-sale Securities					1,419,431,000	1,006,985,000
Net cash provided by (used in) operating activities, continuing operations					290,137,000	(5,993,000)
Net cash provided by (used in) operating activities, discontinued operations					0	(1,759,000)
Net cash provided by (used in) investing activities, discontinued operations					0	4,999,000
Net Cash Provided by (Used in) Discontinued Operations					$ 0	(421,000)
Business Overview [Abstract]
Number of Operating Segments \| segment					2
Mortgage Insurance [Abstract]
Payments for Repurchase of Common Stock					$ 100,188,000	202,000,000
Loss on induced conversion and debt extinguishment (Note 11)		$ 17,397,000		$ 11,000	$ 75,075,000	91,887,000
Stock Repurchase Program, Authorized Amount								$ 125,000,000
Mortgage Insurance Segment
Mortgage Insurance [Abstract]
Private Mortgage Insurance Protects Lenders For Loans Made With Less Than This Maximum Down Payment Percentage		20.00%	20.00%		20.00%
Percentage Of Primary Insurance On Domestic First-Lien Mortgages To Total Risk In Force		97.80%	97.80%		97.80%
Risk In Force		$ 47,300,000,000	$ 47,300,000,000		$ 47,300,000,000
Senior Notes Due 2017
Mortgage Insurance [Abstract]
Debt Instrument, Repurchase Amount							$ 195,500,000
Loss on induced conversion and debt extinguishment (Note 11)			$ 15,000,000
Debt Instrument, Interest Rate, Stated Percentage		9.00%	9.00%		9.00%
Senior Notes Due 2021
Mortgage Insurance [Abstract]
Long-term debt, Gross		$ 350,000,000	$ 350,000,000		$ 350,000,000				$ 350,000,000
Debt Instrument, Interest Rate, Stated Percentage		7.00%	7.00%		7.00%
Convertible Senior Notes Due 2017
Mortgage Insurance [Abstract]
Debt Instrument, Interest Rate, Stated Percentage		3.00%	3.00%		3.00%
Convertible Senior Notes Due 2019
Mortgage Insurance [Abstract]
Debt Instrument, Interest Rate, Stated Percentage		2.25%	2.25%		2.25%
Scenario, Previously Reported [Member]
Basis of Presentation and Business Overview [Line Items]
Proceeds from Sale and Maturity of Fixed-Maturity Investments Available-for-sale						96,684,000
Payments to Acquire Available-for-sale Securities						1,087,461,000
Convertible Debt
Mortgage Insurance [Abstract]
Loss on induced conversion and debt extinguishment (Note 11)					$ 60,100,000
Repayments of Convertible Debt					235,000,000
Convertible Debt \| Convertible Senior Notes Due 2017
Mortgage Insurance [Abstract]
Long-term debt, Gross		$ 22,233,000	$ 22,233,000		22,233,000					$ 52,370,000
Debt Instrument, Repurchase Amount		30,100,000	30,100,000		30,100,000
Convertible Debt \| Convertible Senior Notes Due 2019
Mortgage Insurance [Abstract]
Long-term debt, Gross		68,024,000	68,024,000		68,024,000					$ 389,992,000
Debt Instrument, Repurchase Amount		$ 322,000,000	$ 322,000,000		$ 322,000,000
Reportable Legal Entities [Member] \| Radian Guaranty
Mortgage Insurance [Abstract]
Repayments of Notes Payable	$ 325,000,000
Pool Insurance Mortgage Insurance Product [Member] \| Mortgage Insurance Segment
Mortgage Insurance [Abstract]
Concentration Risk, Percentage					2.10%
Classification Error [Member]
Basis of Presentation and Business Overview [Line Items]
Net Cash Provided by (Used in) Investing Activities						$ 0