Litigation and Contingencies	12 Months Ended
Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Litigation and Contingencies	Litigation and Contingencies Before paying a claim, we review the loan and servicing files to determine the appropriateness of the claim amount. All of our insurance policies provide that we can reduce or deny a claim if the servicer did not comply with its obligations under our insurance policy, including the requirement to mitigate our loss by performing reasonable loss mitigation efforts or, for example, diligently pursuing a foreclosure or bankruptcy relief in a timely manner. We call such reduction of claims submitted to us “curtailments.” In each of 2014 and 2015, curtailments reduced our average claim paid by approximately 6.7%. After we pay a claim, servicers and insureds sometimes object to our curtailments and other adjustments. We review these objections if they are sent to us within 90 days after the claim was paid. When reviewing the loan file associated with a claim, we may determine that we have the right to rescind coverage on the loan. (We refer to insurance rescissions and denials of claims collectively as "rescissions" and variations of that term.) In recent quarters, approximately 5% of claims received in a quarter have been resolved by rescissions, down from the peak of approximately 28% in the first half of 2009. Our loss reserving methodology incorporates our estimates of future rescissions, reversals of rescissions and curtailments. A variance between ultimate actual rescission, reversal and curtailment rates and our estimates, as a result of the outcome of litigation, settlements or other factors, could materially affect our losses. If the insured disputes our right to rescind coverage, we generally engage in discussions in an attempt to settle the dispute. As part of those discussions, we may voluntarily suspend rescissions we believe may be part of a settlement. Certain settlements require GSE approval. The GSEs consented to settlement agreements we entered into with Countrywide Home Loans, Inc. (“CHL”) and its affiliate, Bank of America, N.A., as successor to Countrywide Home Loans Servicing LP, but there is no guarantee they will approve others. We have reached and implemented settlement agreements that do not require GSE approval, but they have not been material in the aggregate. If we are unable to reach a settlement, the outcome of a dispute ultimately would be determined by legal proceedings. Under our policies in effect prior to October 1, 2014, legal proceedings disputing our right to rescind coverage may be brought up to three years after the lender has obtained title to the property (typically through a foreclosure) or the property was sold in a sale that we approved, whichever is applicable, and under our master policy effective October 1, 2014, such proceedings may be brought up to two years from the date of the notice of rescission. In a few jurisdictions there is a longer time to bring such proceedings. Until a liability associated with a settlement agreement or litigation becomes probable and can be reasonably estimated, we consider our claim payment or rescission resolved for financial reporting purposes even though discussions and legal proceedings may have been initiated and are ongoing. Under ASC 450-20, an estimated loss from such discussions and proceedings is accrued for only if we determine that the loss is probable and can be reasonably estimated. The estimated impact that we have recorded is our best estimate of our loss from these matters. If we are not able to implement settlements we consider probable, we intend to defend MGIC vigorously against any related legal proceedings. In addition to the probable settlements for which we have recorded a loss, we are involved in other discussions and/or proceedings with insureds with respect to our claims paying practices. Although it is reasonably possible that when these matters are resolved we will not prevail in all cases, we are unable to make a reasonable estimate or range of estimates of the potential liability. We estimate the maximum exposure associated with matters where a loss is reasonably possible to be approximately $317 million, although we believe we will ultimately resolve these matters for significantly less than this amount. This estimate includes the maximum exposure for losses that we have determined are probable in excess of the provision we have recorded for such losses. The estimates of our maximum exposure referred to above do not include interest or consequential or exemplary damages. Mortgage insurers, including MGIC, have been involved in litigation alleging violations of the anti-referral fee provisions of the Real Estate Settlement Procedures Act, which is commonly known as RESPA, and the notice provisions of the Fair Credit Reporting Act, which is commonly known as FCRA. MGIC’s settlement of class action litigation against it under RESPA became final in October 2003. MGIC settled the named plaintiffs’ claims in litigation against it under FCRA in December 2004, following denial of class certification in June 2004. Since December 2006, class action litigation has been brought against a number of large lenders alleging that their captive mortgage reinsurance arrangements violated RESPA. Beginning in December 2011, MGIC, together with various mortgage lenders and other mortgage insurers, was named as a defendant in twelve lawsuits, alleged to be class actions, filed in various U.S. District Courts. The complaints in all of the cases alleged various causes of action related to the captive mortgage reinsurance arrangements of the mortgage lenders, including that the lenders’ captive reinsurers received excessive premiums in relation to the risk assumed by those captives, thereby violating RESPA. As of the end of the first quarter of 2015, MGIC had been dismissed from all twelve cases. There can be no assurance that we will not be subject to further litigation under RESPA (or FCRA) or that the outcome of any such litigation would not have a material adverse effect on us. In 2013, we entered into a settlement with the CFPB that resolved a federal investigation of MGIC’s participation in captive reinsurance arrangements without the CFPB or the court making any findings of wrongdoing. As part of the settlement, MGIC agreed that it would not enter into any new captive reinsurance agreement or reinsure any new loans under any existing captive reinsurance agreement for a period of ten years. MGIC had voluntarily suspended most of its captive arrangements in 2008 in response to market conditions and GSE requests. In connection with the settlement, MGIC paid a civil penalty of $2.65 million and the court issued an injunction prohibiting MGIC from violating any provisions of RESPA. In 2015, MGIC executed a Consent Order with the Minnesota Department of Commerce that resolved that department’s investigation of captive reinsurance matters without making any findings of wrongdoing. The Consent Order provided, among other things, that MGIC is prohibited from entering into any new captive reinsurance agreement or reinsuring any new loans under any existing captive reinsurance agreement for a period of ten years. Various regulators, including the CFPB, state insurance commissioners and state attorneys general may bring other actions seeking various forms of relief in connection with alleged violations of RESPA. The insurance law provisions of many states prohibit paying for the referral of insurance business and provide various mechanisms to enforce this prohibition. While we believe our practices are in conformity with applicable laws and regulations, it is not possible to predict the eventual scope, duration or outcome of any such reviews or investigations nor is it possible to predict their effect on us or the mortgage insurance industry. Through a non-insurance subsidiary, we utilize our underwriting skills to provide an outsourced underwriting service to our customers known as contract underwriting. As part of the contract underwriting activities, that subsidiary is responsible for the quality of the underwriting decisions in accordance with the terms of the contract underwriting agreements with customers. That subsidiary may be required to provide certain remedies to its customers if certain standards relating to the quality of our underwriting work are not met, and we have an established reserve for such future obligations. Claims for remedies may be made a number of years after the underwriting work was performed. Beginning in the second half of 2009, our subsidiary experienced an increase in claims for contract underwriting remedies, which continued throughout 2012. The related contract underwriting remedy expense was approximately $4 million and $5 million for the years ended December 31, 2014 and 2013, respectively. The underwriting remedy expense for 2015 was approximately $1 million, but may increase in the future. In addition to the matters described above, we are involved in other legal proceedings in the ordinary course of business. In our opinion, based on the facts known at this time, the ultimate resolution of these ordinary course legal proceedings will not have a material adverse effect on our financial position or results of operations. See Note 14 – “Income Taxes” for a description of federal income tax contingencies.

Litigation and Contingencies

Before paying a claim, we review the loan and servicing files to determine the appropriateness of the claim amount. All of our insurance policies provide that we can reduce or deny a claim if the servicer did not comply with its obligations under our insurance policy, including the requirement to mitigate our loss by performing reasonable loss mitigation efforts or, for example, diligently pursuing a foreclosure or bankruptcy relief in a timely manner. We call such reduction of claims submitted to us “curtailments.” In each of 2014 and 2015, curtailments reduced our average claim paid by approximately 6.7%. After we pay a claim, servicers and insureds sometimes object to our curtailments and other adjustments. We review these objections if they are sent to us within 90 days after the claim was paid.

When reviewing the loan file associated with a claim, we may determine that we have the right to rescind coverage on the loan. (We refer to insurance rescissions and denials of claims collectively as "rescissions" and variations of that term.) In recent quarters, approximately 5% of claims received in a quarter have been resolved by rescissions, down from the peak of approximately 28% in the first half of 2009. Our loss reserving methodology incorporates our estimates of future rescissions, reversals of rescissions and curtailments. A variance between ultimate actual rescission, reversal and curtailment rates and our estimates, as a result of the outcome of litigation, settlements or other factors, could materially affect our losses.

If the insured disputes our right to rescind coverage, we generally engage in discussions in an attempt to settle the dispute. As part of those discussions, we may voluntarily suspend rescissions we believe may be part of a settlement. Certain settlements require GSE approval. The GSEs consented to settlement agreements we entered into with Countrywide Home Loans, Inc. (“CHL”) and its affiliate, Bank of America, N.A., as successor to Countrywide Home Loans Servicing LP, but there is no guarantee they will approve others. We have reached and implemented settlement agreements that do not require GSE approval, but they have not been material in the aggregate.

If we are unable to reach a settlement, the outcome of a dispute ultimately would be determined by legal proceedings. Under our policies in effect prior to October 1, 2014, legal proceedings disputing our right to rescind coverage may be brought up to three years after the lender has obtained title to the property (typically through a foreclosure) or the property was sold in a sale that we approved, whichever is applicable, and under our master policy effective October 1, 2014, such proceedings may be brought up to two years from the date of the notice of rescission. In a few jurisdictions there is a longer time to bring such proceedings.

Until a liability associated with a settlement agreement or litigation becomes probable and can be reasonably estimated, we consider our claim payment or rescission resolved for financial reporting purposes even though discussions and legal proceedings may have been initiated and are ongoing. Under ASC 450-20, an estimated loss from such discussions and proceedings is accrued for only if we determine that the loss is probable and can be reasonably estimated. The estimated impact that we have recorded is our best estimate of our loss from these matters. If we are not able to implement settlements we consider probable, we intend to defend MGIC vigorously against any related legal proceedings.

In addition to the probable settlements for which we have recorded a loss, we are involved in other discussions and/or proceedings with insureds with respect to our claims paying practices. Although it is reasonably possible that when these matters are resolved we will not prevail in all cases, we are unable to make a reasonable estimate or range of estimates of the potential liability. We estimate the maximum exposure associated with matters where a loss is reasonably possible to be approximately $317 million, although we believe we will ultimately resolve these matters for significantly less than this amount. This estimate includes the maximum exposure for losses that we have determined are probable in excess of the provision we have recorded for such losses.

The estimates of our maximum exposure referred to above do not include interest or consequential or exemplary damages.

Mortgage insurers, including MGIC, have been involved in litigation alleging violations of the anti-referral fee provisions of the Real Estate Settlement Procedures Act, which is commonly known as RESPA, and the notice provisions of the Fair Credit Reporting Act, which is commonly known as FCRA. MGIC’s settlement of class action litigation against it under RESPA became final in October 2003. MGIC settled the named plaintiffs’ claims in litigation against it under FCRA in December 2004, following denial of class certification in June 2004. Since December 2006, class action litigation has been brought against a number of large lenders alleging that their captive mortgage reinsurance arrangements violated RESPA. Beginning in December 2011, MGIC, together with various mortgage lenders and other mortgage insurers, was named as a defendant in twelve lawsuits, alleged to be class actions, filed in various U.S. District Courts. The complaints in all of the cases alleged various causes of action related to the captive mortgage reinsurance arrangements of the mortgage lenders, including that the lenders’ captive reinsurers received excessive premiums in relation to the risk assumed by those captives, thereby violating RESPA. As of the end of the first quarter of 2015, MGIC had been dismissed from all twelve cases. There can be no assurance that we will not be subject to further litigation under RESPA (or FCRA) or that the outcome of any such litigation would not have a material adverse effect on us.

In 2013, we entered into a settlement with the CFPB that resolved a federal investigation of MGIC’s participation in captive reinsurance arrangements without the CFPB or the court making any findings of wrongdoing. As part of the settlement, MGIC agreed that it would not enter into any new captive reinsurance agreement or reinsure any new loans under any existing captive reinsurance agreement for a period of ten years. MGIC had voluntarily suspended most of its captive arrangements in 2008 in response to market conditions and GSE requests. In connection with the settlement, MGIC paid a civil penalty of $2.65 million and the court issued an injunction prohibiting MGIC from violating any provisions of RESPA.

In 2015, MGIC executed a Consent Order with the Minnesota Department of Commerce that resolved that department’s investigation of captive reinsurance matters without making any findings of wrongdoing. The Consent Order provided, among other things, that MGIC is prohibited from entering into any new captive reinsurance agreement or reinsuring any new loans under any existing captive reinsurance agreement for a period of ten years.

Various regulators, including the CFPB, state insurance commissioners and state attorneys general may bring other actions seeking various forms of relief in connection with alleged violations of RESPA. The insurance law provisions of many states prohibit paying for the referral of insurance business and provide various mechanisms to enforce this prohibition. While we believe our practices are in conformity with applicable laws and regulations, it is not possible to predict the eventual scope, duration or outcome of any such reviews or investigations nor is it possible to predict their effect on us or the mortgage insurance industry.

Through a non-insurance subsidiary, we utilize our underwriting skills to provide an outsourced underwriting service to our customers known as contract underwriting. As part of the contract underwriting activities, that subsidiary is responsible for the quality of the underwriting decisions in accordance with the terms of the contract underwriting agreements with customers. That subsidiary may be required to provide certain remedies to its customers if certain standards relating to the quality of our underwriting work are not met, and we have an established reserve for such future obligations. Claims for remedies may be made a number of years after the underwriting work was performed. Beginning in the second half of 2009, our subsidiary experienced an increase in claims for contract underwriting remedies, which continued throughout 2012. The related contract underwriting remedy expense was approximately $4 million and $5 million for the years ended December 31, 2014 and 2013, respectively. The underwriting remedy expense for 2015 was approximately $1 million, but may increase in the future.

In addition to the matters described above, we are involved in other legal proceedings in the ordinary course of business. In our opinion, based on the facts known at this time, the ultimate resolution of these ordinary course legal proceedings will not have a material adverse effect on our financial position or results of operations.

See Note 14 – “Income Taxes” for a description of federal income tax contingencies.