MGIC Investment (MTG) 10-Q 7 May 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	Apr. 30, 2019
Document and Entity Information [Abstract]
Entity Registrant Name	MGIC INVESTMENT CORP
Entity Central Index Key	0000876437
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		355,985,627
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Investment portfolio:
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	$ 5,287,360	$ 5,151,987
Equity securities, at fair value (cost 2019 - $4,016; 2018 - $3,993)	4,057	3,932
Other invested assets, at cost	3,100	3,100
Total investment portfolio	5,294,517	5,159,019
Cash and cash equivalents	259,351	151,892
Restricted cash and cash equivalents	3,161	3,146
Accrued investment income	46,699	48,001
Reinsurance recoverable on loss reserves	31,875	33,328
Reinsurance recoverable on paid losses	3,069	2,948
Premiums receivable	51,596	55,090
Home office and equipment, net	50,388	51,734
Deferred insurance policy acquisition costs	17,630	17,888
Deferred income taxes, net	39,440	69,184
Other assets	72,371	85,572
Total assets	5,870,097	5,677,802
Liabilities:
Loss reserves	655,264	674,019
Unearned premiums	404,504	409,985
Federal Home Loan Bank advance	155,000	155,000
Senior notes	420,002	419,713
Convertible junior subordinated debentures	256,872	256,872
Other liabilities	162,272	180,322
Total liabilities	2,053,914	2,095,911
Contingencies
Shareholders’ equity:
Common stock (one dollar par value, shares authorized 1,000,000; shares issued 2019 - 371,353; 2018 - 371,353; shares outstanding 2019 - 355,986; 2018 - 355,371	371,353	371,353
Paid-in capital	1,856,236	1,862,536
Treasury stock at cost (shares 2019 - 15,367; 2018 - 15,982)	(169,129)	(175,059)
Accumulated other comprehensive loss, net of tax	(41,493)	(124,214)
Retained earnings	1,799,216	1,647,275
Total shareholders’ equity	3,816,183	3,581,891
Total liabilities and shareholders’ equity	$ 5,870,097	$ 5,677,802

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Fixed maturities, amortized cost	$ 5,229,535	$ 5,196,784
Equity securities, cost	$ 4,016	$ 3,993
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	371,353,000	371,353,000
Common stock, shares outstanding (in shares)	355,986,000	355,371,000
Treasury stock, shares at cost (in shares)	15,367,000	15,982,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Premiums written:
Direct	$ 273,897	$ 270,034
Assumed	1,107	92
Ceded	(30,723)	(33,220)
Net premiums written	244,281	236,906
Decrease (increase) in unearned premiums, net	5,480	(4,799)
Net premiums earned	249,761	232,107
Investment income, net of expenses	40,585	32,121
Net realized investment losses	(526)	(329)
Other revenue	1,830	1,871
Total revenues	291,650	265,770
Losses and expenses:
Losses incurred, net	39,063	23,850
Amortization of deferred policy acquisition costs	2,478	2,572
Other underwriting and operating expenses, net	45,940	46,090
Interest expense	13,233	13,233
Total losses and expenses	100,714	85,745
Income before tax	190,936	180,025
Provision for income taxes	38,995	36,388
Net income	$ 151,941	$ 143,637
Earnings per share:
Basic (in dollars per share)	$ 0.43	$ 0.39
Diluted (in dollars per share)	$ 0.42	$ 0.38
Weighted average common shares outstanding - basic (in shares)	355,653	370,908
Weighted average common shares outstanding - diluted (in shares)	376,667	391,562

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 151,941	$ 143,637
Other comprehensive income (loss), net of tax:
Change in unrealized investment gains and losses	81,071	(64,453)
Benefit plan adjustments	1,650	494
Other comprehensive income (loss), net of tax	82,721	(63,959)
Comprehensive income	$ 234,662	$ 79,678

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common stock	Paid-in capital	Treasury stock	Accumulated other comprehensive (loss) income	Retained earnings
Balance, beginning of period at Dec. 31, 2017		$ 370,567	$ 1,850,582	$ 0	$ (43,801)	$ 977,178
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net common stock issued under share-based compensation plans		781	(8,854)
Reissuance of treasury stock, net under share-based compensation plans			0	0
Equity compensation			5,272
Other comprehensive income (loss), net of tax	$ (63,959)				(63,959)
Net income	143,637					143,637
Balance, end of period at Mar. 31, 2018	3,231,403	371,348	1,847,000	0	(107,760)	1,120,815
Balance, beginning of period at Dec. 31, 2018	3,581,891	371,353	1,862,536	(175,059)	(124,214)	1,647,275
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net common stock issued under share-based compensation plans		0	0
Reissuance of treasury stock, net under share-based compensation plans			(11,582)	5,930
Equity compensation			5,282
Other comprehensive income (loss), net of tax	82,721				82,721
Net income	151,941					151,941
Balance, end of period at Mar. 31, 2019	$ 3,816,183	$ 371,353	$ 1,856,236	$ (169,129)	$ (41,493)	$ 1,799,216

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net income	$ 151,941	$ 143,637
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	11,908	15,833
Deferred tax expense	7,755	39,388
Net realized investment losses	526	329
Change in certain assets and liabilities:
Accrued investment income	1,302	937
Reinsurance recoverable on loss reserves	1,453	3,000
Reinsurance recoverable on paid losses	(121)	154
Premium receivable	3,494	1,344
Deferred insurance policy acquisition costs	258	(87)
Profit commission receivable	(2,836)	377
Loss reserves	(18,755)	(61,464)
Unearned premiums	(5,481)	4,754
Return premium accrual	(3,100)	(5,500)
Current income taxes	30,983	(3,149)
Other, net	(14,446)	(5,587)
Net cash provided by operating activities	164,881	133,966
Cash flows from investing activities:
Purchases of investments	(348,746)	(209,497)
Proceeds from sales of investments	106,010	10,844
Proceeds from maturity of fixed income securities	202,929	155,605
Additions to property and equipment	(308)	(5,208)
Net cash used in investing activities	(40,115)	(48,256)
Cash flows from financing activities:
Repurchase of common stock	(11,640)	0
Payment of withholding taxes related to share-based compensation net share settlement	(5,652)	(8,073)
Net cash used in financing activities	(17,292)	(8,073)
Net increase in cash and cash equivalents and restricted cash and cash equivalents	107,474	77,637
Cash and cash equivalents and restricted cash and cash equivalents at beginning of period	155,038	99,851
Cash and cash equivalents and restricted cash and cash equivalents at end of period	$ 262,512	$ 177,488

Nature of Business and Basis of

Nature of Business and Basis of Presentation	3 Months Ended
	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business and Basis of Presentation	Nature of Business and Basis of Presentation MGIC Investment Corporation is a holding company which, through Mortgage Guaranty Insurance Corporation (“MGIC”), is principally engaged in the mortgage insurance business. We provide mortgage insurance to lenders throughout the United States and to government sponsored entities to protect against loss from defaults on low down payment residential mortgage loans. MGIC Assurance Corporation (“MAC”) and MGIC Indemnity Corporation (“MIC”), insurance subsidiaries of MGIC, provide insurance for certain mortgages under Fannie Mae and Freddie Mac (the “GSEs”) credit risk transfer programs. The accompanying unaudited consolidated financial statements of MGIC Investment Corporation and its wholly-owned subsidiaries have been prepared in accordance with the instructions to Form 10-Q as prescribed by the Securities and Exchange Commission (“SEC”) for interim reporting and do not include all of the other information and disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). These statements should be read in conjunction with the consolidated financial statements and notes thereto for the year ended December 31, 2018 included in our 2018 Annual Report on Form 10-K. As used below, “we,” “our” and “us” refer to MGIC Investment Corporation’s consolidated operations or to MGIC Investment Corporation, as the context requires. In the opinion of management, the accompanying financial statements include all adjustments, consisting primarily of normal recurring accruals, necessary to fairly state our consolidated financial position and consolidated results of operations for the periods indicated. The consolidated results of operations for the interim period may not be indicative of the results that may be expected for the year ending December 31, 2019 . Substantially all of our insurance written since 2008 has been for loans purchased by the GSEs. The current private mortgage insurer eligibility requirements ("PMIERs") of the GSEs include financial requirements, as well as business, quality control and certain transactional approval requirements. The financial requirements of the PMIERs require a mortgage insurer’s "Available Assets" (generally only the most liquid assets of an insurer) to equal or exceed its "Minimum Required Assets" (which are based on an insurer's book of insurance in force, calculated from tables of factors with several risk dimensions and subject to a floor amount). Based on our interpretation of the PMIERs, as of March 31, 2019 , MGIC’s Available Assets are in excess of its Minimum Required Assets; and MGIC is in compliance with the financial requirements of the PMIERs and eligible to insure loans purchased by the GSEs. Reclassifications Certain reclassifications to 2018 amounts have been made in the accompanying financial statements to conform to the 2019 presentation. Subsequent events We have considered subsequent events through the date of this filing. Refer to Note 4 - “Reinsurance” for information regarding our notice of termination of our 2015 quota share reinsurance agreement (“2015 QSR Transaction”).

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Significant Accounting Policies	Significant Accounting Policies Income taxes Deferred income taxes are provided under the liability method, which recognizes the future tax effects of temporary differences between amounts reported in the consolidated financial statements and the tax bases of these items. The estimated tax effects are computed at the enacted federal statutory income tax rate. Changes in tax laws, rates, regulations, and policies or the final determination of tax audits or examinations, could materially affect our estimates and can be significant to our operating results. We evaluate the realizability of the deferred tax assets based on the weight of all available positive and negative evidence. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that all or some portion of the deferred tax assets will not be realized. The recognition of a tax position is determined using a two-step approach, a more-likely-than-not threshold for recognition and derecognition, and a measurement attribute that is the greatest amount of benefit that is cumulatively greater than 50% likely of being realized. When evaluating a tax position for recognition and measurement, we presume that the tax position will be examined by the relevant taxing authority that has full knowledge of all relevant information. We recognize interest accrued and penalties related to unrecognized tax benefits in our provision for income taxes. Federal tax law permits mortgage guaranty insurance companies to deduct from taxable income, subject to certain limitations, the amounts added to contingency loss reserves, which are recorded for regulatory purposes. The amounts we deduct must generally be included in taxable income in the tenth subsequent year. The deduction is allowed only to the extent that we purchase and hold U.S. government noninterest bearing tax and loss bonds in an amount equal to the tax benefit attributable to the deduction. We account for these purchases as a payment of current federal income tax. Recent accounting and reporting developments Accounting standards effective in 2019, or early adopted, and relevant to our financial statements Accounting Standard Update (“ASU”) 2016-02 - Leases In February 2016, the Financial Accounting Standards Board (“FASB”) amended the previous leasing standard and created ASC 842, Leases. ASC 842 requires a lessee to recognize a right-of-use asset and lease liability for substantially all leases. Effective for the quarter ended March 31, 2019, we adopted the updated guidance for leases and also elected to apply all practical expedients applicable to us in the updated guidance for transition of leases in effect at adoption, including using hindsight to determine the lease term of existing leases, the option to not reassess whether an existing contract is a lease or contains a lease and whether the lease is an operating or finance lease. The adoption of the updated guidance resulted in the recognition of an immaterial right-of-use asset as part of other assets and a lease liability as part of other liabilities in the consolidated balance sheet as of March 31, 2019. The adoption of the updated guidance did not have a material effect on our consolidated results of operations or liquidity. Our minimum future operating lease payments as of March 31, 2019 totaled $2.6 million . Prospective Accounting Standards Table 2.1 shows the relevant new amendments to accounting standards, which are not yet effective or adopted. Standard / Interpretation Table 2.1 Amended Standards Effective date ASC 326 Financial Instruments - Credit Losses • ASU 2016-13 - Measurement of Credit Losses on Financial Instruments January 1, 2020 ASC 820 Fair Value Measurement • ASU 2018-13 - Changes to the Disclosure Requirements for Fair Value Measurements January 1, 2020 ASC 715 Compensation - Retirement Benefits • ASU 2018-14 - Changes to the Disclosure Requirements for Defined Benefit Plans January 1, 2021 Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued updated guidance that requires immediate recognition of estimated credit losses expected to occur over the remaining life of many financial instruments. Entities will be required to utilize a current expected credit losses (“CECL”) methodology that incorporates their forecast of future economic conditions into their loss estimate unless such forecast is not reasonable and supportable, in which case the entity will revert to historical loss experience. Any allowance for CECL reduces the amortized cost basis of the financial instrument to the amount an entity expects to collect. Credit losses relating to available-for-sale fixed maturity securities are to be recorded through an allowance for credit losses, rather than a write-down of the asset, with the amount of the allowance limited to the amount by which fair value is less than amortized cost. In addition, the length of time a security has been in an unrealized loss position will no longer impact the determination of whether a credit loss exists. The updated guidance is not prescriptive about certain aspects of estimating expected credit losses, including the specific methodology to use, and therefore will require significant judgment in application. The updated guidance is effective for annual periods beginning after December 15, 2019, including interim periods within those annual periods. Early adoption is permitted for annual and interim periods in fiscal years beginning after December 15, 2018. We are currently evaluating the impacts the adoption of this guidance will have on our consolidated financial statements and disclosures, but do not expect it to have a material impact. Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued updated guidance that changes the disclosure requirements for fair value measurements. The updated guidance removed the requirement to disclose the amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy; the policy for timing of transfers between levels; and the valuation processes for Level 3 fair value measurements. The updated guidance clarifies that the measurement uncertainty disclosure is to communicate information about the uncertainty in measurements as of the reporting date. Further, the updated guidance will require disclosure of changes in unrealized gains and losses for the period included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the reporting period; and the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. The updated guidance is effective for annual periods beginning after December 15, 2019, including interim periods within those annual periods. An entity is permitted to early adopt any guidance that removed or modified disclosures upon issuance of this update and to delay adoption of the additional disclosures until its effective date. We are currently evaluating the impacts the adoption of this guidance will have on our consolidated financial statement disclosures, but do not expect it to have a material impact. Changes to the Disclosure Requirements for Defined Benefit Plans In August 2018, the FASB issued amendments to modify the disclosure requirements for defined benefit plans. The updated guidance removed the requirements to identify amounts that are expected to be reclassified out of accumulated other comprehensive income and recognized as components of net periodic benefit cost in the coming year and the effects of a one-percentage-point change in assumed health care cost trend rates on service and interest cost and on the postretirement benefit obligation. The updated guidance added disclosures for the weighted-average interest crediting rates for cash balance plans and other plans with interest crediting rates and explanations for significant gains and losses related to changes in the benefit obligation for the period. The updated guidance is effective for annual periods beginning after December 15, 2020. Early adoption is permitted. An entity should apply the amendments on a retrospective basis to all periods presented. We are currently evaluating the impacts the adoption of this guidance will have on our consolidated financial statement disclosures, but do not expect it to have a material impact.

Debt

Debt	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Debt	Debt Debt obligations The par value of our long-term debt obligations and their aggregate carrying values as of March 31, 2019 and December 31, 2018 are presented in table 3.1 below. Long-term debt obligations Table 3.1 (In millions) March 31, December 31, FHLB Advance - 1.91%, due February 2023 $ 155.0 $ 155.0 5.75% Notes, due August 2023 (par value: $425 million) 420.0 419.7 9% Debentures, due April 2063 (1) 256.9 256.9 Long-term debt, carrying value $ 831.9 $ 831.6 (1) Convertible at any time prior to maturity at the holder’s option, at an initial conversion rate, which is subject to adjustment, of 74.0741 shares per $1,000 principal amount, representing an initial conversion price of approximately $13.50 per share. If a holder elects to convert its debentures, deferred interest owed on the debentures being converted is also converted into shares of our common stock. The conversion rate for any deferred interest is based on the average price that our shares traded at during a 5 -day period immediately prior to the election to convert. In lieu of issuing shares of common stock upon conversion of the debentures, we may, at our option, make a cash payment to converting holders for all or some of the shares of our common stock otherwise issuable upon conversion. The 5.75% Senior Notes (“ 5.75% Notes”), 9% Convertible Junior Subordinated Debentures (“ 9% Debentures”), and any amounts drawn on our revolving credit facility, are obligations of our holding company, MGIC Investment Corporation, and not of its subsidiaries. In addition to interest on amounts drawn, the unused portion of our revolving credit facility is subject to recurring commitment fees, which are reflected in interest payments. The Federal Home Loan Bank Advance (the “FHLB Advance”) is an obligation of MGIC. Interest payments Interest payments for each of the three months ended March 31, 2019 and 2018 were $13.1 million .

Reinsurance

Reinsurance	3 Months Ended
	Mar. 31, 2019
Reinsurance Disclosures [Abstract]
Reinsurance	Reinsurance The reinsurance agreements to which we are a party, excluding captive agreements (which were immaterial), are discussed below. The effect of all of our reinsurance agreements on premiums earned and losses incurred is shown in table 4.1 below. Reinsurance Table 4.1 Three Months Ended March 31, (In thousands) 2019 2018 Premiums earned: Direct $ 279,613 $ 265,251 Assumed 872 121 Ceded (30,724 ) (33,265 ) Net premiums earned $ 249,761 $ 232,107 Losses incurred: Direct $ 40,804 $ 31,501 Assumed (67 ) 90 Ceded (1,674 ) (7,741 ) Losses incurred, net $ 39,063 $ 23,850 Quota share reinsurance We utilize quota share reinsurance to manage our exposure to losses resulting from our mortgage guaranty insurance policies and to provide reinsurance capital credit under the PMIERs. Each of the reinsurers under our QSR Transactions has an insurer financial strength rating of A- or better by Standard and Poor’s Rating Services, A.M. Best or both. 2019 QSR Transaction. We entered into a QSR transaction with a group of unaffiliated reinsurers with an effective date of January 1, 2019 (“2019 QSR Transaction”), which provides coverage on eligible new insurance written in 2019. Under the 2019 QSR Transaction, we will cede losses and premiums on or after the effective date through December 31, 2030, at which time the agreement expires. Early termination of the agreement can be elected by us effective December 31, 2021 or bi-annually thereafter, for a fee, or under specified scenarios for no fee upon prior written notice, including if we will receive less than 90% of the full credit amount under the PMIERs for the risk ceded in any required calculation period. The structure of the 2019 QSR Transaction is a 30% quota share, with a one-time option, elected by us, to reduce the cede rate to either 25% or 20% effective July 1, 2020, or bi-annually thereafter, for a fee, for all policies covered, with a 20% ceding commission as well as a profit commission. Generally, under the 2019 QSR Transaction, we will receive a profit commission provided that the loss ratio on the loans covered under the agreement remains below 62% . 2018 and prior QSR Transactions. See Note 9 of Notes to Consolidated Financial Statements in our 2018 Form 10-K for more information about our QSR Transactions entered into prior to 2019. 2015 QSR Transaction. We have terminated a portion of our 2015 QSR Transaction effective June 30, 2019 and have agreed to terms on an amended quota share reinsurance agreement with certain participants from the existing reinsurance panel that effectively reduces the quota share cede rate from 30% to 15% on the remaining eligible insurance. The amended quota share reinsurance agreement is subject to GSE approval. When the amended terms are effective we will generally receive a profit commission provided that the loss ratio on the covered loans remains below 68% . Table 4.2 below presents a summary of our quota share reinsurance agreements for the three months ended March 31, 2019 and 2018. Quota Share Reinsurance Table 4.2 Three Months Ended March 31, (In thousands) 2019 2018 Ceded premiums written and earned, net of profit commission (1) $ 28,164 $ 33,036 Ceded losses incurred 1,676 7,788 Ceding commissions (2) 13,409 12,645 Profit commission 38,881 30,189 (1) Premiums are ceded on an earned and received basis as defined in the agreements. (2) Ceding commissions are reported within Other underwriting and operating expenses, net on the consolidated statements of operations. Under the terms of the QSR Transactions, ceded premiums, ceding commission and profit commission are settled net on a quarterly basis. The ceded premiums due after deducting the related ceding commission and profit commission is reported within “Other liabilities” on the consolidated balance sheets. The reinsurance recoverable on loss reserves related to our QSR Transactions was $31.8 million as of March 31, 2019 and $33.2 million as of December 31, 2018 . The reinsurance recoverable balance is secured by funds on deposit from the reinsurers which are based on the funding requirements of PMIERs that address ceded risk. Excess of loss reinsurance Home Re. We have entered into an aggregate excess of loss reinsurance agreement with Home Re. At the time the Home Re agreement was entered into, we assessed whether Home Re was a variable interest entity (“VIE”). A VIE is a legal entity that does not have sufficient equity at risk to finance its activities without additional subordinated financial support or is structured such that equity investors lack the ability to make sufficient decisions relating to the entity’s operations through voting rights or do not substantively participate in gains and losses of the entity. We concluded that Home Re is a VIE. However, given that MGIC (1) does not have the unilateral power to direct the activities that most significantly affect Home Re’s economic performance and (2) does not have the obligation to absorb losses or the right to receive benefits of Home Re, consolidation of Home Re is not required. The amount of monthly reinsurance coverage premium ceded will fluctuate due to change in one-month LIBOR and changes in money market rates that affect investment income collected on the assets in the reinsurance trust. As the reinsurance premium will vary based on changes in these rates, we concluded that the reinsurance agreement contains an embedded derivative that is accounted for separately as a freestanding derivative. The fair value of the derivative at March 31, 2019, and the change in fair value from December 31, 2018, was not material to our consolidated balance sheet and consolidated statement of operations as of and for the three months ended March 31, 2019, respectively. Total ceded premiums were $2.5 million for the three months ended March 31, 2019. We are required to disclose our maximum exposure to loss, which we consider to be an amount that we could be required to record in our statement of operations, as a result of our involvement with this VIE. As of March 31, 2019 and December 31, 2018, we did not have material exposure to the VIE as we have no investment in the VIE and had no reinsurance claim payments due from the VIE under our reinsurance agreement. We are unable to determine the timing or extent of claims from losses that are ceded under the reinsurance agreement. The VIE assets are deposited in a reinsurance trust for the benefit of MGIC that will be the source of reinsurance claim payments to MGIC. The purpose of the reinsurance trust is to provide security to MGIC for the obligations of the VIE under the reinsurance agreement. The trustee of the reinsurance trust, a recognized provider of corporate trust services, has established a segregated account within the reinsurance trust for the benefit of MGIC, pursuant to the trust agreement. The trust agreement is governed by, and construed in accordance with, the laws of the State of New York. If the trustee of the reinsurance trust failed to distribute claim payments to us as provided in the reinsurance trust, we would incur a loss related to our losses ceded under the reinsurance agreement and deemed unrecoverable. We are also unable to determine the impact such possible failure by the trustee to perform pursuant to the reinsurance trust agreement may have on our consolidated financial statements. As a result, we are unable to quantify our maximum exposure to loss related to our involvement with the VIE. MGIC has certain termination rights under the reinsurance agreement should its claims not be paid. We consider our exposure to loss from our reinsurance agreement with the VIE to be remote. The following presents the total assets of Home Re as of March 31, 2019 and December 31, 2018 . Home Re total assets Table 4.3 (In thousands) Home Re entity (Issue date) Total VIE Assets March 31, 2019 Home Re 2018-01 Ltd. (Oct - 2018) $ 318,636 December 31, 2018 Home Re 2018-01 Ltd. (Oct - 2018) $ 318,636 The assets of Home Re provide capital credit under the PMIERs financial requirements (see Note 1 - Nature of Business and Basis of Presentation” ). A decline in the assets available to pay claims would reduce the capital credit available to MGIC.

Litigation and Contingencies

Litigation and Contingencies	3 Months Ended
	Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Litigation and Contingencies	Litigation and Contingencies Before paying an insurance claim, we review the loan and servicing files to determine the appropriateness of the claim amount. When reviewing the files, 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 addition, our insurance policies generally provide that we can reduce or deny a claim if the servicer did not comply with its obligations under our insurance policy. We call such reduction of claims “curtailments.” In recent quarters, an immaterial percentage of claims received in a quarter have been resolved by rescissions. In 2018, and the first quarter of 2019, curtailments reduced our average claim paid by approximately 5.8% and 3.9% , respectively. Our loss reserving methodology incorporates our estimates of future rescissions, curtailments, and reversals of rescissions and curtailments. A variance between ultimate actual rescission, curtailment and reversal rates and our estimates, as a result of the outcome of litigation, settlements or other factors, could materially affect our losses. When the insured disputes our right to rescind coverage or curtail claims, we generally engage in discussions in an attempt to settle the dispute. If we are unable to reach a settlement, the outcome of a dispute ultimately may be determined by legal proceedings. Under ASC 450-20, until a liability associated with settlement discussions or legal proceedings becomes probable and can be reasonably estimated, we consider our claim payment or rescission resolved for financial reporting purposes and do not accrue an estimated loss. Where we have determined that a loss is probable and can be reasonably estimated, we have recorded our best estimate of our probable loss, including recording a probable loss of $23.5 million in the first quarter of 2019. Until settlement negotiations or legal proceedings for which we have recorded a probable loss are concluded, it is reasonably possible that we will record an additional loss. In addition to matters for which we have recorded a probable 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 all of 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 $266.2 million more than the amount of probable loss we have recorded. This estimate of maximum exposure is based upon currently available information and is subject to significant judgment, numerous assumptions and known and unknown uncertainties, and will include an amount for matters for which we have recorded a probable loss until such matters are concluded. The matters underlying the estimate of maximum exposure will change from time to time. This estimate of our maximum exposure does not include interest or consequential or exemplary damages. Mortgage insurers, including MGIC, have been involved in litigation and regulatory actions related to alleged 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. While these proceedings in the aggregate have not resulted in material liability for MGIC, there can be no assurance that the outcome of future proceedings, if any, under these laws would not have a material adverse effect on us. In addition, 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. The underwriting remedy expense for 2018 and the first three months of 2019 was immaterial to our consolidated financial statements. 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 consolidated results of operations.

Earnings per Share

Earnings per Share	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Earnings per Share	Earnings per Share Basic earnings per share (“EPS”) is calculated by dividing net income by the weighted average number of shares of common stock outstanding. For purposes of calculating basic EPS, vested restricted stock and restricted stock units (“RSUs”) are considered outstanding. Diluted EPS includes the components of basic EPS and also gives effect to dilutive common stock equivalents. We calculate diluted EPS using the treasury stock method and if-converted method. Under the treasury stock method, diluted EPS reflects the potential dilution that could occur if unvested RSUs result in the issuance of common stock. Under the if-converted method, diluted EPS reflects the potential dilution that could occur if our 9% Debentures result in the issuance of common stock. The determination of potentially issuable shares does not consider the satisfaction of the conversion requirements and the shares are included in the determination of diluted EPS as of the beginning of the period, if dilutive. Table 6.1 reconciles the numerators and denominators used to calculate basic and diluted EPS. Earnings per share Table 6.1 Three Months Ended March 31, (In thousands, except per share data) 2019 2018 Basic earnings per share: Net income $ 151,941 $ 143,637 Weighted average common shares outstanding - basic 355,653 370,908 Basic earnings per share $ 0.43 $ 0.39 Diluted earnings per share: Net income $ 151,941 $ 143,637 Interest expense, net of tax (1) : 9% Debentures 4,566 4,566 Diluted income available to common shareholders $ 156,507 $ 148,203 Weighted average common shares outstanding - basic 355,653 370,908 Effect of dilutive securities: Unvested RSUs 1,986 1,626 9% Debentures 19,028 19,028 Weighted average common shares outstanding - diluted 376,667 391,562 Diluted earnings per share $ 0.42 $ 0.38 (1) The periods ended March 31, 2019 and 2018 were tax-effected at a rate of 21%.

Investments

Investments	3 Months Ended
	Mar. 31, 2019
Investments [Abstract]
Investments	Investments Fixed income securities The amortized cost, gross unrealized gains and losses, and fair value of investments in fixed income securities classified as available-for-sale at March 31, 2019 and December 31, 2018 are shown in tables 7.1a and 7.1b below. Details of fixed income securities by category as of March 31, 2019 Table 7.1a (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized (Losses) (1) Fair Value U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 167,821 $ 910 $ (589 ) $ 168,142 Obligations of U.S. states and political subdivisions 1,611,092 58,372 (2,226 ) 1,667,238 Corporate debt securities 2,442,354 23,363 (9,648 ) 2,456,069 Asset backed securities (“ABS”) 217,469 1,045 (33 ) 218,481 Residential mortgage backed securities (“RMBS”) 188,201 143 (7,859 ) 180,485 Commercial mortgage backed securities (“CMBS”) 272,074 1,808 (4,599 ) 269,283 Collateralized loan obligations (“CLO”) 330,524 — (2,862 ) 327,662 Total fixed income securities $ 5,229,535 $ 85,641 $ (27,816 ) $ 5,287,360 Details of fixed income securities by category as of December 31, 2018 Table 7.1b (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized (Losses) (1) Fair Value U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 167,655 $ 597 $ (1,076 ) $ 167,176 Obligations of U.S. states and political subdivisions 1,701,826 29,259 (10,985 ) 1,720,100 Corporate debt securities 2,439,173 2,103 (40,514 ) 2,400,762 ABS 111,953 226 (146 ) 112,033 RMBS 189,238 32 (10,309 ) 178,961 CMBS 276,352 888 (9,580 ) 267,660 CLOs 310,587 2 (5,294 ) 305,295 Total fixed income securities $ 5,196,784 $ 33,107 $ (77,904 ) $ 5,151,987 (1) At March 31, 2019 and December 31, 2018 , there were no other-than-temporary impairment losses recorded in other comprehensive income. We had $13.6 million and $13.5 million of investments at fair value on deposit with various states as of March 31, 2019 and December 31, 2018 , respectively, due to regulatory requirements of those state insurance departments. The amortized cost and fair values of fixed income securities at March 31, 2019 , by contractual maturity, are shown in table 7.2 below. Actual maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Because most ABS, RMBS, CMBS, and CLOs provide for periodic payments throughout their lives, they are listed in separate categories. Fixed income securities maturity schedule Table 7.2 March 31, 2019 (In thousands) Amortized cost Fair Value Due in one year or less $ 375,772 $ 375,241 Due after one year through five years 1,748,834 1,753,881 Due after five years through ten years 948,568 966,862 Due after ten years 1,148,093 1,195,465 4,221,267 4,291,449 ABS 217,469 218,481 RMBS 188,201 180,485 CMBS 272,074 269,283 CLOs 330,524 327,662 Total as of March 31, 2019 $ 5,229,535 $ 5,287,360 Proceeds from sales of fixed income securities classified as available-for-sale were $106.0 million and $10.8 million during the three months ended March 31, 2019 and 2018 , respectively. Gross gains of $0.7 million and $0.1 million and gross losses of $1.3 million and $0.3 million were realized on those sales during the three months ended March 31, 2019 and 2018 , respectively. During the three months ended March 31, 2019 , we recorded other-than-temporary impairment (“OTTI”) losses of $0.1 million . During the three months ended March 31, 2018 , there were no OTTI losses recognized. Equity securities The cost and fair value of investments in equity securities at March 31, 2019 and December 31, 2018 are shown in tables 7.3a and 7.3b below. Details of equity security investments as of March 31, 2019 Table 7.3a (In thousands) Cost Gross Gains Gross Losses Fair Value Equity securities $ 4,016 $ 60 $ (19 ) $ 4,057 Details of equity security investments as of December 31, 2018 Table 7.3b (In thousands) Cost Gross Gains Gross Losses Fair Value Equity securities $ 3,993 $ 11 $ (72 ) $ 3,932 For the three months ended March 31, 2019 , we recognized $0.1 million of net gains on equity securities still held as of March 31, 2019 . For the three months ended March 31, 2018, we recognized $0.1 million of net losses on equity securities still held as of March 31, 2018. Other invested assets Other invested assets include an investment in Federal Home Loan Bank (“FHLB”) stock that is carried at cost, which due to its nature approximates fair value. Ownership of FHLB stock provides access to a secured lending facility, and our current FHLB Advance amount is secured by eligible collateral whose fair value is maintained at a minimum of 102% of the outstanding principal balance. As of March 31, 2019 , that collateral consisted of fixed income securities included in our total investment portfolio, and cash and cash equivalents, with a total fair value of $171.6 million . Unrealized investment losses Tables 7.4a and 7.4b below summarize, for all available-for-sale investments in an unrealized loss position at March 31, 2019 and December 31, 2018 , the aggregate fair value and gross unrealized loss by the length of time those securities have been continuously in an unrealized loss position. The fair value amounts reported in tables 7.4a and 7.4b are estimated using the process described in Note 8 - “Fair Value Measurements” to these consolidated financial statements and in Note 3 - “Significant Accounting Policies” of the notes to the consolidated financial statements in our 2018 Annual Report on Form 10-K. Unrealized loss aging for securities by type and length of time as of March 31, 2019 Table 7.4a Less Than 12 Months 12 Months or Greater Total (In thousands) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses U.S. Treasury securities and obligations of U.S. government corporations and agencies $ — $ — $ 68,951 $ (589 ) $ 68,951 $ (589 ) Obligations of U.S. states and political subdivisions 17,518 (444 ) 213,567 (1,782 ) 231,085 (2,226 ) Corporate debt securities 149,625 (1,315 ) 852,102 (8,333 ) 1,001,727 (9,648 ) ABS 18,444 (33 ) — — 18,444 (33 ) RMBS — — 175,437 (7,859 ) 175,437 (7,859 ) CMBS 9,757 (94 ) 189,785 (4,505 ) 199,542 (4,599 ) CLOs 317,663 (2,862 ) — — 317,663 (2,862 ) Total $ 513,007 $ (4,748 ) $ 1,499,842 $ (23,068 ) $ 2,012,849 $ (27,816 ) Unrealized loss aging for securities by type and length of time as of December 31, 2018 Table 7.4b Less Than 12 Months 12 Months or Greater Total (In thousands) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 23,710 $ (15 ) $ 69,146 $ (1,061 ) $ 92,856 $ (1,076 ) Obligations of U.S. states and political subdivisions 316,655 (3,875 ) 358,086 (7,110 ) 674,741 (10,985 ) Corporate debt securities 1,272,279 (18,130 ) 785,627 (22,384 ) 2,057,906 (40,514 ) ABS 51,324 (146 ) — — 51,324 (146 ) RMBS 24 — 178,573 (10,309 ) 178,597 (10,309 ) CMBS 65,704 (1,060 ) 163,272 (8,520 ) 228,976 (9,580 ) CLOs 296,497 (5,294 ) — — 296,497 (5,294 ) Total $ 2,026,193 $ (28,520 ) $ 1,554,704 $ (49,384 ) $ 3,580,897 $ (77,904 ) The unrealized losses in all categories of our investments at March 31, 2019 and December 31, 2018 were primarily caused by changes in interest rates between the time of purchase and the respective fair value measurement date. There were 420 and 721 securities in an unrealized loss position at March 31, 2019 and December 31, 2018 , respectively.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Recurring fair value measurements The following describes the valuation methodologies generally used by the independent pricing sources, or by us, to measure financial instruments at fair value, including the general classification of such financial instruments pursuant to the valuation hierarchy. Level 1 measurements • Fixed income securities: Consist of primarily U.S. Treasury securities with valuations derived from quoted prices for identical instruments in active markets that we can access. • Equity securities: Consist of actively traded, exchange-listed equity securities with valuations derived from quoted prices for identical assets in active markets that we can access. • Other: Consists of money market funds with valuations derived from quoted prices for identical assets in active markets that we can access. Level 2 measurements • Fixed income securities: Corporate Debt & U.S. Government and Agency Bonds are valued by surveying the dealer community, obtaining relevant trade data, benchmark quotes and spreads and incorporating this information into the valuation process. Obligations of U.S. States & Political Subdivisions are valued by tracking, capturing, and analyzing quotes for active issues and trades reported via the Municipal Securities Rulemaking Board records. Daily briefings and reviews of current economic conditions, trading levels, spread relationships, and the slope of the yield curve provide further data for evaluation. Residential Mortgage-Backed Securities ("RMBS") are valued by monitoring interest rate movements, and other pertinent data daily. Incoming market data is enriched to derive spread, yield and/or price data as appropriate, enabling known data points to be extrapolated for valuation application across a range of related securities. Commercial Mortgage-Backed Securities ("CMBS") are valued using techniques that reflect market participants’ assumptions and maximize the use of relevant observable inputs including quoted prices for similar assets, benchmark yield curves and market corroborated inputs. Evaluation uses regular reviews of the inputs for securities covered, including executed trades, broker quotes, credit information, collateral attributes and/or cash flow waterfall as applicable. Asset-Backed Securities ("ABS") are valued using spreads and other information solicited from market buy-and-sell-side sources, including primary and secondary dealers, portfolio managers, and research analysts. Cash flows are generated for each tranche, benchmark yields are determined, and deal collateral performance and tranche level attributes including trade activity, bids, and offers are applied, resulting in tranche specific prices. Collateralized loan obligations ("CLO") are valued by evaluating manager rating, seniority in the capital structure, assumptions about prepayment, default and recovery and their impact on cash flow generation. Loan level net asset values are determined and aggregated for tranches and as a final step prices are checked against available recent trade activity. Level 3 measurements • Real estate acquired is valued at the lower of our acquisition cost or a percentage of the appraised value. The percentage applied to the appraised value is based upon our historical sales experience adjusted for current trends. Assets measured at fair value, by hierarchy level, as of March 31, 2019 and December 31, 2018 are shown in tables 8.1a and 8.1b below. The fair value of the assets is estimated using the process described above, and more fully in Note 3 - “Significant Accounting Policies” of the notes to the consolidated financial statements in our 2018 Annual Report on Form 10-K. Assets carried at fair value by hierarchy level as of March 31, 2019 Table 8.1a (In thousands) Total Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 168,142 $ 42,479 $ 125,663 $ — Obligations of U.S. states and political subdivisions 1,667,238 — 1,667,238 — Corporate debt securities 2,456,069 — 2,456,069 — ABS 218,481 — 218,481 — RMBS 180,485 — 180,485 — CMBS 269,283 — 269,283 — CLOs 327,662 — 327,662 — Total fixed income securities 5,287,360 42,479 5,244,881 — Equity securities 4,057 4,057 — — Other (1) 205,444 205,444 — — Real estate acquired (2) 11,639 — — 11,639 Total $ 5,508,500 $ 251,980 $ 5,244,881 $ 11,639 Assets carried at fair value by hierarchy level as of December 31, 2018 Table 8.1b (In thousands) Total Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 167,176 $ 42,264 $ 124,912 $ — Obligations of U.S. states and political subdivisions 1,720,100 — 1,720,087 13 Corporate debt securities 2,400,762 — 2,400,762 — ABS 112,033 — 112,033 — RMBS 178,961 — 178,961 — CMBS 267,660 — 267,660 — CLOs 305,295 — 305,295 — Total fixed income securities 5,151,987 42,264 5,109,710 13 Equity securities 3,932 3,932 — — Other (1) 96,403 96,403 — — Real estate acquired (2) 14,535 — — 14,535 Total $ 5,266,857 $ 142,599 $ 5,109,710 $ 14,548 (1) Consists of money market funds included in “Cash and Cash Equivalents” and “Restricted Cash and Cash Equivalents” on the consolidated balance sheets. (2) Real estate acquired through claim settlement, which is held for sale, is reported in “Other assets” on the consolidated balance sheets. Reconciliations of Level 3 assets For assets measured at fair value using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances for the three months ended March 31, 2019 and 2018 is shown in tables 8.2a and 8.2b below. As shown in table 8.2b below, we transferred our FHLB stock out of Level 3 assets, and it is carried at cost, which approximates fair value, on our consolidated balance sheet in “Other invested assets.” There were no losses included in earnings for those periods attributable to the change in unrealized losses on assets still held at the end of the applicable period. Fair value roll-forward for financial instruments classified as Level 3 for the three months ended March 31, 2019 Table 8.2a (In thousands) Fixed income Equity Securities Total Investments Real Estate Acquired Balance at December 31, 2018 $ 13 $ — $ 13 $ 14,535 Purchases — — — 8,084 Sales (13 ) — (13 ) (10,872 ) Included in earnings and reported as losses incurred, net — — — (108 ) Balance at March 31, 2019 $ — $ — $ — $ 11,639 Fair value roll-forward for financial instruments classified as Level 3 for the three months ended March 31, 2018 Table 8.2b (In thousands) Fixed income Equity Total Real Estate Balance at December 31, 2017 271 4,268 4,539 12,713 Transfers out of Level 3 — (3,100 ) (3,100 ) — Purchases — — — 5,894 Sales (17 ) — (17 ) (8,870 ) Included in earnings and reported as losses incurred, net — — — 341 Balance at March 31, 2018 $ 254 $ 1,168 $ 1,422 $ 10,078 Certain financial instruments, including insurance contracts, are excluded from these fair value disclosure requirements. The carrying values of cash and cash equivalents (Level 1) and accrued investment income (Level 2) approximated their fair values. Additional fair value disclosures related to our investment portfolio are included in Note 7 – “Investments.” Financial assets and liabilities not measured at fair value Other invested assets include an investment in FHLB stock that is carried at cost, which due to restrictions that require it to be redeemed or sold only to the security issuer at par value, approximates fair value. The fair value of other invested assets is categorized as Level 2. Financial liabilities include our outstanding debt obligations. The fair values of our 5.75% Notes and 9% Debentures were based on observable market prices. The fair value of the FHLB Advance was estimated using cash flows discounted at current incremental borrowing rates for similar borrowing arrangements. In all cases the fair values of the financial liabilities below are categorized as Level 2. Table 8.3 presents the carrying value and fair value of our financial assets and liabilities disclosed, but not carried, at fair value at March 31, 2019 and December 31, 2018 . Financial assets and liabilities not measured at fair value Table 8.3 March 31, 2019 December 31, 2018 (In thousands) Carrying Value Fair Value Carrying Value Fair Value Financial assets Other invested assets $ 3,100 $ 3,100 $ 3,100 $ 3,100 Financial liabilities FHLB Advance $ 155,000 $ 153,133 $ 155,000 $ 150,551 5.75% Senior Notes 420,002 449,387 419,713 425,791 9% Convertible Junior Subordinated Debentures 256,872 332,580 256,872 338,069 Total financial liabilities $ 831,874 $ 935,100 $ 831,585 $ 914,411

Other Comprehensive Income

Other Comprehensive Income	3 Months Ended
	Mar. 31, 2019
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Other Comprehensive Income	Other Comprehensive Income The pretax and related income tax (expense) benefit components of our other comprehensive income (loss) for the three months ended March 31, 2019 and 2018 are included in table 9.1 below. Components of other comprehensive income (loss) Table 9.1 Three Months Ended March 31, (In thousands) 2019 2018 Net unrealized investment gains (losses) arising during the period $ 102,621 $ (81,587 ) Income tax (expense) benefit (21,550 ) 17,134 Net of taxes 81,071 (64,453 ) Net changes in benefit plan assets and obligations 2,089 625 Income tax expense (439 ) (131 ) Net of taxes 1,650 494 Total other comprehensive income (loss) 104,710 (80,962 ) Total income tax (expense) benefit (21,989 ) 17,003 Total other comprehensive income (loss), net of tax $ 82,721 $ (63,959 ) The pretax and related income tax benefit (expense) components of the amounts reclassified from our accumulated other comprehensive loss (“AOCL”) to our consolidated statements of operations for the three months ended March 31, 2019 and 2018 are included in table 9.2 below. Reclassifications from AOCL Table 9.2 Three Months Ended March 31, (In thousands) 2019 2018 Reclassification adjustment for net realized (losses) (1) $ (2,679 ) $ (91 ) Income tax benefit 563 19 Net of taxes (2,116 ) (72 ) Reclassification adjustment related to benefit plan assets and obligations (2) (2,089 ) (625 ) Income tax benefit (expense) 439 131 Net of taxes (1,650 ) (494 ) Total reclassifications (4,768 ) (716 ) Total income tax benefit 1,002 150 Total reclassifications, net of tax $ (3,766 ) $ (566 ) (1) Increases (decreases) Net realized investment (losses) gains on the consolidated statements of operations. (2) Decreases (increases) Other underwriting and operating expenses, net on the consolidated statements of operations. A rollforward of AOCL for the three months ended March 31, 2019 , including amounts reclassified from AOCL, are included in table 9.3 below. Rollforward of AOCL Table 9.3 Three Months Ended March 31, 2019 (In thousands) Net unrealized gains and (losses) on available-for-sale securities Net benefit plan assets and (obligations) recognized in shareholders' equity Total AOCL Balance, December 31, 2018, net of tax $ (35,389 ) $ (88,825 ) $ (124,214 ) Other comprehensive income before reclassifications 78,955 — 78,955 Less: Amounts reclassified from AOCL (2,116 ) (1,650 ) (3,766 ) Balance, March 31, 2019, net of tax $ 45,682 $ (87,175 ) $ (41,493 )

Benefit Plans

Benefit Plans	3 Months Ended
	Mar. 31, 2019
Retirement Benefits [Abstract]
Benefit Plans	Benefit Plans Table 10.1 provides the components of net periodic benefit cost for our pension, supplemental executive retirement and other postretirement benefit plans for the three months ended March 31, 2019 and 2018 . Components of net periodic benefit cost Table 10.1 Three Months Ended March 31, Pension and Supplemental Executive Retirement Plans Other Postretirement Benefit Plans (In thousands) 2019 2018 2019 2018 Service cost $ 1,996 $ 2,562 $ 312 $ 270 Interest cost 3,955 3,782 291 214 Expected return on plan assets (4,908 ) (5,570 ) (1,445 ) (1,588 ) Amortization of net actuarial losses/(gains) 2,167 1,785 — (46 ) Amortization of prior service cost/(credit) (70 ) (87 ) (8 ) (1,026 ) Net periodic benefit cost (benefit) $ 3,140 $ 2,472 $ (850 ) $ (2,176 ) We currently intend to make contributions totaling $10.7 million to our qualified pension plan and supplemental executive retirement plan in 2019.

Loss Reserves

Loss Reserves	3 Months Ended
	Mar. 31, 2019
Insurance Loss Reserves [Abstract]
Loss Reserves	Loss Reserves We establish reserves to recognize the estimated liability for losses and loss adjustment expenses (“LAE”) related to defaults on insured mortgage loans. Loss reserves are established by estimating the number of loans in our inventory of delinquent loans that will result in a claim payment, which is referred to as the claim rate, and further estimating the amount of the claim payment, which is referred to as claim severity. Estimation of losses is inherently judgmental. The conditions that affect the claim rate and claim severity include the current and future state of the domestic economy, including unemployment and the current and future strength of local housing markets; exposure on insured loans; the amount of time between default and claim filing; and curtailments and rescissions. The actual amount of the claim payments may be substantially different than our loss reserve estimates. Our estimates could be adversely affected by several factors, including a deterioration of regional or national economic conditions, including unemployment, leading to a reduction in borrowers’ income and thus their ability to make mortgage payments, and a drop in housing values which may affect borrower willingness to continue to make mortgage payments when the value of the home is below the mortgage balance. Changes to our estimates could result in a material impact to our consolidated results of operations and financial position, even in a stable economic environment. The “Losses incurred” section of table 11.1 below shows losses incurred on delinquencies that occurred in the current year and in prior years. The amount of losses incurred relating to delinquencies that occurred in the current year represents the estimated amount to be ultimately paid on such delinquencies. The amount of losses incurred relating to delinquencies that occurred in prior years represents the difference between the actual claim rate and severity associated with those delinquencies resolved in the current year compared to the estimated claim rate and severity at the prior year-end, as well as a re-estimation of amounts to be ultimately paid on delinquencies continuing from the end of the prior year. This re-estimation of the claim rate and severity is the result of our review of current trends in the delinquent inventory, such as percentages of delinquencies that have resulted in a claim, the amount of the claims relative to the average loan exposure, changes in the relative level of delinquencies by geography and changes in average loan exposure. Losses incurred on delinquencies that occurred in the current year decreased in the first three months of 2019 compared to the same period in 2018 , due to a decrease in the number of new delinquencies, net of related cures and a decrease in the estimated claim rate on delinquencies that occurred in the current year. For the three months ended March 31, 2019 and 2018 , we experienced favorable loss reserve development on previously received delinquencies. This was, in large part, due to the resolution of approximately 32% and 31% , respectively, of the prior year delinquent inventory, with lower claim rates due to improved cure rates. The favorable loss reserve development resulting from a reduction in the estimated claim rate was partially offset in the three months ended March 31, 2019 by the recognition of a probable loss of $23.5 million related to litigation of our claims paying practices, and for the three months ended March 31, 2018 , by an increase in our severity assumption on previously received delinquencies. The “Losses paid” section of table 11.1 below shows the amount of losses paid on delinquencies that occurred in the current year and losses paid on delinquencies that occurred in prior years. For several years, the average time it took to receive a claim associated with a delinquency had increased significantly from our historical experience of approximately twelve months. This was, in part, due to new loss mitigation protocols established by servicers and to changes in some state foreclosure laws that may include, for example, a requirement for additional review and/or mediation processes. In recent quarters, we have experienced a decline in the average time servicers are utilizing to process foreclosures, which has reduced the average time to receive a claim associated with new delinquent notices that do not cure. All else being equal, the longer the period between delinquency and claim filing, the greater the severity. During the first three months of 2018, our losses paid included $7 million paid upon commutation of coverage of pools of non-performing loans (“NPLs”). The commutations reduced our delinquent inventory by 224 delinquencies and had no material impact on our losses incurred, net. Premium refunds Our estimate of premiums to be refunded on expected claim payments is accrued for separately in “Other Liabilities” on our consolidated balance sheets and approximated $37 million and $40 million at March 31, 2019 and December 31, 2018 , respectively. Table 11.1 provides a reconciliation of beginning and ending loss reserves as of and for the three months ended March 31, 2019 and 2018 . Development of reserves for losses and loss adjustment expenses Table 11.1 Three Months Ended March 31, (In thousands) 2019 2018 Reserve at beginning of period $ 674,019 $ 985,635 Less reinsurance recoverable 33,328 48,474 Net reserve at beginning of period 640,691 937,161 Losses incurred: Losses and LAE incurred in respect of delinquency notices received in: Current year 47,488 59,070 Prior years (1) (8,425 ) (35,220 ) Total losses incurred 39,063 23,850 Losses paid: Losses and LAE paid in respect of delinquency notices received in: Current year — 95 Prior years 56,365 81,983 Reinsurance terminations — 236 Total losses paid 56,365 82,314 Net reserve at end of period 623,389 878,697 Plus reinsurance recoverables 31,875 45,474 Reserve at end of period $ 655,264 $ 924,171 (1) A negative number for prior year losses incurred indicates a redundancy of prior year loss reserves. See the following table for more information about prior year loss development. The prior year development of the reserves in the first three months of 2019 and 2018 is reflected in table 11.2 below. Reserve development on previously received delinquencies Table 11.2 Three Months Ended March 31, (In millions) 2019 2018 Decrease in estimated claim rate on primary defaults $ (31 ) $ (47 ) Increase in estimated severity on primary defaults — 16 Change in estimates related to pool reserves, LAE reserves, reinsurance, and other 23 (4 ) Total prior year loss development (1) $ (8 ) $ (35 ) (1) A negative number for prior year loss development indicates a redundancy of prior year loss reserves. Delinquent inventory A rollforward of our primary delinquent inventory for the three months ended March 31, 2019 and 2018 appears in table 11.3 below. The information concerning new notices and cures is compiled from monthly reports received from loan servicers. The level of new notice and cure activity reported in a particular month can be influenced by, among other things, the date on which a servicer generates its report, the accuracy of the data provided by servicers, the number of business days in a month, transfers of servicing between loan servicers and whether all servicers have provided the reports in a given month. Delinquent inventory rollforward Table 11.3 Three Months Ended March 31, 2019 2018 Delinquent inventory at beginning of period 32,898 46,556 New notices 13,611 14,623 Cures (14,348 ) (18,073 ) Paid claims (1,188 ) (1,571 ) Rescissions and denials (52 ) (68 ) Other items removed from inventory — (224 ) Delinquent inventory at end of period 30,921 41,243 The decrease in the primary delinquent inventory experienced during 2019 and 2018 was generally across all markets and primarily in book years 2008 and prior. Historically as a delinquency ages it becomes more likely to result in a claim. Hurricane activity New delinquent notice activity increased in the fourth quarter of 2017 because of hurricane activity that primarily impacted Puerto Rico, Texas, and Florida in the third quarter of 2017. Many of the loans from the hurricane impacted areas remained delinquent through the period ending March 31, 2018 and are shown in the 4-11 months delinquent category in table 11.4 . The majority of the delinquent notices received from the hurricane activity cured as of December 31, 2018. Table 11.4 below shows the number of consecutive months a borrower is delinquent. Primary delinquent inventory - consecutive months delinquent Table 11.4 March 31, 2019 December 31, 2018 March 31, 2018 3 months or less 8,568 9,829 8,770 4-11 months 9,997 9,655 16,429 12 months or more (1) 12,356 13,414 16,044 Total 30,921 32,898 41,243 3 months or less 28 % 30 % 21 % 4-11 months 32 % 29 % 40 % 12 months or more 40 % 41 % 39 % Total 100 % 100 % 100 % Primary claims received inventory included in ending delinquent inventory: 665 809 819 (1) Approximately 38% , 38% , and 44% of the primary delinquent inventory delinquent for 12 consecutive months or more has been delinquent for at least 36 consecutive months as of March 31, 2019 , December 31, 2018 , and March 31, 2018 , respectively. Pool insurance delinquent inventory decreased to 723 at March 31, 2019 from 859 at December 31, 2018 , and 1,200 at March 31, 2018 . Claims paying practices Our loss reserving methodology incorporates our estimates of future rescissions and curtailments. A variance between ultimate actual rescission and curtailment rates and our estimates, as a result of the outcome of litigation, settlements or other factors, could materially affect our losses. Our estimate of premiums to be refunded on expected future rescissions is accrued for separately and is included in “Other liabilities” on our consolidated balance sheets. For information about discussions and legal proceedings with customers with respect to our claims paying practices see Note 5 – “Litigation and Contingencies.”

Shareholders' Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2019
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Shareholders’ Equity Share repurchase programs In March 2019, our board of directors authorized an additional share repurchase program under which we may repurchase up to $200 million of our common stock through the end of 2020. We have approximately $25 million remaining on an existing share repurchase authorization announced in April 2018 that remains in place through the end of 2019. Repurchases may be made from time to time on the open market or through privately negotiated transactions. The repurchase program may be suspended for periods or discontinued at any time. We did not repurchase any shares during the three months ended March 31, 2019.

Share-Based Compensation

Share-Based Compensation	3 Months Ended
	Mar. 31, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation We have certain share-based compensation plans. Under the fair value method, compensation cost is measured at the grant date based on the fair value of the award and is recognized over the service period which generally corresponds to the vesting period. Awards under our plans generally vest over periods ranging from one to three years . Table 13.1 shows the number of shares granted to employees and the weighted average fair value per share during the periods presented (shares in thousands). Restricted stock grants Table 13.1 Three Months Ended March 31, 2019 2018 Shares Granted Weighted Average Share Fair Value Shares Granted Weighted Average Share Fair Value RSUs subject to performance conditions 1,378 $ 11.76 1,239 $ 15.80 RSUs subject only to service conditions 412 11.76 412 15.71

Statutory Information

Statutory Information	3 Months Ended
	Mar. 31, 2019
Statutory Capital [Abstract]
Statutory Information	Statutory Information Statutory Capital Requirements The insurance laws of 16 jurisdictions, including Wisconsin, our domiciliary state, require a mortgage insurer to maintain a minimum amount of statutory capital relative to the net risk in force (or a similar measure) in order for the mortgage insurer to continue to write new business. We refer to these requirements as the “State Capital Requirements.” While they vary among jurisdictions, the most common State Capital Requirements allow for a maximum risk-to-capital ratio of 25 to 1 . A risk-to-capital ratio will increase if (i) the percentage decrease in capital exceeds the percentage decrease in insured risk, or (ii) the percentage increase in capital is less than the percentage increase in insured risk. Wisconsin does not regulate capital by using a risk-to-capital measure but instead requires a minimum policyholder position (“MPP”). The “policyholder position” of a mortgage insurer is its net worth or surplus, contingency reserve and a portion of the reserves for unearned premiums. At March 31, 2019 , MGIC’s risk-to-capital ratio was 8.9 to 1 , below the maximum allowed by the jurisdictions with State Capital Requirements, and its policyholder position was $2.7 billion above the required MPP of $1.3 billion . In calculating our risk-to-capital ratio and MPP, we are allowed full credit for the risk ceded under our QSR Transactions with a group of unaffiliated reinsurers. It is possible that under the revised State Capital Requirements discussed below, MGIC will not be allowed full credit for the risk ceded to the reinsurers. If MGIC is not allowed an agreed level of credit under either the State Capital Requirements or the financial requirements of the PMIERs, MGIC may terminate the reinsurance transactions, without penalty. At this time, we expect MGIC to continue to comply with the current State Capital Requirements; however, matters that could negatively affect such compliance are discussed in the rest of these consolidated financial statement footnotes. At March 31, 2019 , the risk-to-capital ratio of our combined insurance operations (which includes a reinsurance affiliate) was 9.6 to 1 . The NAIC plans to revise the minimum capital and surplus requirements for mortgage insurers that are provided for in its Mortgage Guaranty Insurance Model Act. In May 2016, a working group of state regulators released an exposure draft of a risk-based capital framework to establish capital requirements for mortgage insurers, although no date has been established by which the NAIC must propose revisions to the capital requirements and certain items have not yet been completely addressed by the framework, including the treatment of ceded risk, minimum capital floors, and action level triggers. Currently, we believe that the PMIERs contain more restrictive capital requirements than the draft Mortgage Guaranty Insurance Model Act in most circumstances. While MGIC currently meets the State Capital Requirements of Wisconsin and all other jurisdictions, it could be prevented from writing new business in the future in all jurisdictions if it fails to meet the State Capital Requirements of Wisconsin, or it could be prevented from writing new business in a particular jurisdiction if it fails to meet the State Capital Requirements of that jurisdiction, and in each case MGIC does not obtain a waiver of such requirements. It is possible that regulatory action by one or more jurisdictions, including those that do not have specific State Capital Requirements, may prevent MGIC from continuing to write new insurance in such jurisdictions. If we are unable to write business in a particular jurisdiction, lenders may be unwilling to procure insurance from us anywhere. In addition, a lender’s assessment of the future ability of our insurance operations to meet the State Capital Requirements or the PMIERs may affect its willingness to procure insurance from us. A possible future failure by MGIC to meet the State Capital Requirements or the PMIERs will not necessarily mean that MGIC lacks sufficient resources to pay claims on its insurance liabilities. While we believe MGIC has sufficient claims paying resources to meet its claim obligations on its insurance in force on a timely basis, matters that could negatively affect MGIC’s claims paying resources are discussed in the rest of these consolidated financial statement footnotes. Dividend restrictions In the first quarter of 2019, MGIC paid a $70 million dividend to our holding company. MGIC is subject to statutory regulations as to payment of dividends. The maximum amount of dividends that MGIC may pay in any twelve-month period without such dividends being subject to regulatory disapproval by the OCI is the lesser of adjusted statutory net income or 10% of statutory policyholders’ surplus as of the preceding calendar year end. Adjusted statutory net income is defined for this purpose to be the greater of statutory net income, net of realized investment gains, for the calendar year preceding the date of the dividend or statutory net income, net of realized investment gains, for the three calendar years preceding the date of the dividend less dividends paid within the first two of the preceding three calendar years. The OCI recognizes only statutory accounting principles prescribed, or practices permitted by the State of Wisconsin for determining and reporting the financial condition and results of operations of an insurance company. The OCI has adopted certain prescribed accounting practices that differ from those found in other states. Specifically, Wisconsin domiciled companies record changes in their contingency reserves through their income statement as a change in underwriting deduction. As a result, in periods in which MGIC is increasing contingency reserves, statutory net income is lowered.

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Income taxes	Income taxes Deferred income taxes are provided under the liability method, which recognizes the future tax effects of temporary differences between amounts reported in the consolidated financial statements and the tax bases of these items. The estimated tax effects are computed at the enacted federal statutory income tax rate. Changes in tax laws, rates, regulations, and policies or the final determination of tax audits or examinations, could materially affect our estimates and can be significant to our operating results. We evaluate the realizability of the deferred tax assets based on the weight of all available positive and negative evidence. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that all or some portion of the deferred tax assets will not be realized. The recognition of a tax position is determined using a two-step approach, a more-likely-than-not threshold for recognition and derecognition, and a measurement attribute that is the greatest amount of benefit that is cumulatively greater than 50% likely of being realized. When evaluating a tax position for recognition and measurement, we presume that the tax position will be examined by the relevant taxing authority that has full knowledge of all relevant information. We recognize interest accrued and penalties related to unrecognized tax benefits in our provision for income taxes. Federal tax law permits mortgage guaranty insurance companies to deduct from taxable income, subject to certain limitations, the amounts added to contingency loss reserves, which are recorded for regulatory purposes. The amounts we deduct must generally be included in taxable income in the tenth subsequent year. The deduction is allowed only to the extent that we purchase and hold U.S. government noninterest bearing tax and loss bonds in an amount equal to the tax benefit attributable to the deduction. We account for these purchases as a payment of current federal income tax.
Prospective Accounting Standards	Recent accounting and reporting developments Accounting standards effective in 2019, or early adopted, and relevant to our financial statements Accounting Standard Update (“ASU”) 2016-02 - Leases In February 2016, the Financial Accounting Standards Board (“FASB”) amended the previous leasing standard and created ASC 842, Leases. ASC 842 requires a lessee to recognize a right-of-use asset and lease liability for substantially all leases. Effective for the quarter ended March 31, 2019, we adopted the updated guidance for leases and also elected to apply all practical expedients applicable to us in the updated guidance for transition of leases in effect at adoption, including using hindsight to determine the lease term of existing leases, the option to not reassess whether an existing contract is a lease or contains a lease and whether the lease is an operating or finance lease. The adoption of the updated guidance resulted in the recognition of an immaterial right-of-use asset as part of other assets and a lease liability as part of other liabilities in the consolidated balance sheet as of March 31, 2019. The adoption of the updated guidance did not have a material effect on our consolidated results of operations or liquidity. Our minimum future operating lease payments as of March 31, 2019 totaled $2.6 million . Prospective Accounting Standards Table 2.1 shows the relevant new amendments to accounting standards, which are not yet effective or adopted. Standard / Interpretation Table 2.1 Amended Standards Effective date ASC 326 Financial Instruments - Credit Losses • ASU 2016-13 - Measurement of Credit Losses on Financial Instruments January 1, 2020 ASC 820 Fair Value Measurement • ASU 2018-13 - Changes to the Disclosure Requirements for Fair Value Measurements January 1, 2020 ASC 715 Compensation - Retirement Benefits • ASU 2018-14 - Changes to the Disclosure Requirements for Defined Benefit Plans January 1, 2021 Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued updated guidance that requires immediate recognition of estimated credit losses expected to occur over the remaining life of many financial instruments. Entities will be required to utilize a current expected credit losses (“CECL”) methodology that incorporates their forecast of future economic conditions into their loss estimate unless such forecast is not reasonable and supportable, in which case the entity will revert to historical loss experience. Any allowance for CECL reduces the amortized cost basis of the financial instrument to the amount an entity expects to collect. Credit losses relating to available-for-sale fixed maturity securities are to be recorded through an allowance for credit losses, rather than a write-down of the asset, with the amount of the allowance limited to the amount by which fair value is less than amortized cost. In addition, the length of time a security has been in an unrealized loss position will no longer impact the determination of whether a credit loss exists. The updated guidance is not prescriptive about certain aspects of estimating expected credit losses, including the specific methodology to use, and therefore will require significant judgment in application. The updated guidance is effective for annual periods beginning after December 15, 2019, including interim periods within those annual periods. Early adoption is permitted for annual and interim periods in fiscal years beginning after December 15, 2018. We are currently evaluating the impacts the adoption of this guidance will have on our consolidated financial statements and disclosures, but do not expect it to have a material impact. Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued updated guidance that changes the disclosure requirements for fair value measurements. The updated guidance removed the requirement to disclose the amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy; the policy for timing of transfers between levels; and the valuation processes for Level 3 fair value measurements. The updated guidance clarifies that the measurement uncertainty disclosure is to communicate information about the uncertainty in measurements as of the reporting date. Further, the updated guidance will require disclosure of changes in unrealized gains and losses for the period included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the reporting period; and the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. The updated guidance is effective for annual periods beginning after December 15, 2019, including interim periods within those annual periods. An entity is permitted to early adopt any guidance that removed or modified disclosures upon issuance of this update and to delay adoption of the additional disclosures until its effective date. We are currently evaluating the impacts the adoption of this guidance will have on our consolidated financial statement disclosures, but do not expect it to have a material impact. Changes to the Disclosure Requirements for Defined Benefit Plans In August 2018, the FASB issued amendments to modify the disclosure requirements for defined benefit plans. The updated guidance removed the requirements to identify amounts that are expected to be reclassified out of accumulated other comprehensive income and recognized as components of net periodic benefit cost in the coming year and the effects of a one-percentage-point change in assumed health care cost trend rates on service and interest cost and on the postretirement benefit obligation. The updated guidance added disclosures for the weighted-average interest crediting rates for cash balance plans and other plans with interest crediting rates and explanations for significant gains and losses related to changes in the benefit obligation for the period. The updated guidance is effective for annual periods beginning after December 15, 2020. Early adoption is permitted. An entity should apply the amendments on a retrospective basis to all periods presented. We are currently evaluating the impacts the adoption of this guidance will have on our consolidated financial statement disclosures, but do not expect it to have a material impact.

Significant Accounting Polici_3

Significant Accounting Policies Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Schedule of Prospective Accounting Standards, Not Yet Effective Or Adopted	Table 2.1 shows the relevant new amendments to accounting standards, which are not yet effective or adopted. Standard / Interpretation Table 2.1 Amended Standards Effective date ASC 326 Financial Instruments - Credit Losses • ASU 2016-13 - Measurement of Credit Losses on Financial Instruments January 1, 2020 ASC 820 Fair Value Measurement • ASU 2018-13 - Changes to the Disclosure Requirements for Fair Value Measurements January 1, 2020 ASC 715 Compensation - Retirement Benefits • ASU 2018-14 - Changes to the Disclosure Requirements for Defined Benefit Plans January 1, 2021

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Long-term debt	The par value of our long-term debt obligations and their aggregate carrying values as of March 31, 2019 and December 31, 2018 are presented in table 3.1 below. Long-term debt obligations Table 3.1 (In millions) March 31, December 31, FHLB Advance - 1.91%, due February 2023 $ 155.0 $ 155.0 5.75% Notes, due August 2023 (par value: $425 million) 420.0 419.7 9% Debentures, due April 2063 (1) 256.9 256.9 Long-term debt, carrying value $ 831.9 $ 831.6 (1) Convertible at any time prior to maturity at the holder’s option, at an initial conversion rate, which is subject to adjustment, of 74.0741 shares per $1,000 principal amount, representing an initial conversion price of approximately $13.50 per share. If a holder elects to convert its debentures, deferred interest owed on the debentures being converted is also converted into shares of our common stock. The conversion rate for any deferred interest is based on the average price that our shares traded at during a 5 -day period immediately prior to the election to convert. In lieu of issuing shares of common stock upon conversion of the debentures, we may, at our option, make a cash payment to converting holders for all or some of the shares of our common stock otherwise issuable upon conversion.

Reinsurance (Tables)

Reinsurance (Tables)	3 Months Ended
	Mar. 31, 2019
Reinsurance Disclosures [Abstract]
Effect of reinsurance agreement	The effect of all of our reinsurance agreements on premiums earned and losses incurred is shown in table 4.1 below. Reinsurance Table 4.1 Three Months Ended March 31, (In thousands) 2019 2018 Premiums earned: Direct $ 279,613 $ 265,251 Assumed 872 121 Ceded (30,724 ) (33,265 ) Net premiums earned $ 249,761 $ 232,107 Losses incurred: Direct $ 40,804 $ 31,501 Assumed (67 ) 90 Ceded (1,674 ) (7,741 ) Losses incurred, net $ 39,063 $ 23,850
Effect of quota share reinsurance agreements on premiums earned and losses incurred	Table 4.2 below presents a summary of our quota share reinsurance agreements for the three months ended March 31, 2019 and 2018. Quota Share Reinsurance Table 4.2 Three Months Ended March 31, (In thousands) 2019 2018 Ceded premiums written and earned, net of profit commission (1) $ 28,164 $ 33,036 Ceded losses incurred 1,676 7,788 Ceding commissions (2) 13,409 12,645 Profit commission 38,881 30,189 (1) Premiums are ceded on an earned and received basis as defined in the agreements. (2) Ceding commissions are reported within Other underwriting and operating expenses, net on the consolidated statements of operations.
Schedule of total assets of Home Re	The following presents the total assets of Home Re as of March 31, 2019 and December 31, 2018 . Home Re total assets Table 4.3 (In thousands) Home Re entity (Issue date) Total VIE Assets March 31, 2019 Home Re 2018-01 Ltd. (Oct - 2018) $ 318,636 December 31, 2018 Home Re 2018-01 Ltd. (Oct - 2018) $ 318,636

Earnings per Share (Tables)

Earnings per Share (Tables)	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Calculation of earnings (loss) per share	Table 6.1 reconciles the numerators and denominators used to calculate basic and diluted EPS. Earnings per share Table 6.1 Three Months Ended March 31, (In thousands, except per share data) 2019 2018 Basic earnings per share: Net income $ 151,941 $ 143,637 Weighted average common shares outstanding - basic 355,653 370,908 Basic earnings per share $ 0.43 $ 0.39 Diluted earnings per share: Net income $ 151,941 $ 143,637 Interest expense, net of tax (1) : 9% Debentures 4,566 4,566 Diluted income available to common shareholders $ 156,507 $ 148,203 Weighted average common shares outstanding - basic 355,653 370,908 Effect of dilutive securities: Unvested RSUs 1,986 1,626 9% Debentures 19,028 19,028 Weighted average common shares outstanding - diluted 376,667 391,562 Diluted earnings per share $ 0.42 $ 0.38 (1) The periods ended March 31, 2019 and 2018 were tax-effected at a rate of 21%.

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2019
Investments [Abstract]
Amortized cost, gross unrealized gains and losses and fair value of fixed income securities	The amortized cost, gross unrealized gains and losses, and fair value of investments in fixed income securities classified as available-for-sale at March 31, 2019 and December 31, 2018 are shown in tables 7.1a and 7.1b below. Details of fixed income securities by category as of March 31, 2019 Table 7.1a (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized (Losses) (1) Fair Value U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 167,821 $ 910 $ (589 ) $ 168,142 Obligations of U.S. states and political subdivisions 1,611,092 58,372 (2,226 ) 1,667,238 Corporate debt securities 2,442,354 23,363 (9,648 ) 2,456,069 Asset backed securities (“ABS”) 217,469 1,045 (33 ) 218,481 Residential mortgage backed securities (“RMBS”) 188,201 143 (7,859 ) 180,485 Commercial mortgage backed securities (“CMBS”) 272,074 1,808 (4,599 ) 269,283 Collateralized loan obligations (“CLO”) 330,524 — (2,862 ) 327,662 Total fixed income securities $ 5,229,535 $ 85,641 $ (27,816 ) $ 5,287,360 Details of fixed income securities by category as of December 31, 2018 Table 7.1b (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized (Losses) (1) Fair Value U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 167,655 $ 597 $ (1,076 ) $ 167,176 Obligations of U.S. states and political subdivisions 1,701,826 29,259 (10,985 ) 1,720,100 Corporate debt securities 2,439,173 2,103 (40,514 ) 2,400,762 ABS 111,953 226 (146 ) 112,033 RMBS 189,238 32 (10,309 ) 178,961 CMBS 276,352 888 (9,580 ) 267,660 CLOs 310,587 2 (5,294 ) 305,295 Total fixed income securities $ 5,196,784 $ 33,107 $ (77,904 ) $ 5,151,987 (1) At March 31, 2019 and December 31, 2018 , there were no other-than-temporary impairment losses recorded in other comprehensive income.
Amortized cost and fair values of fixed income securities by contractual maturity	The amortized cost and fair values of fixed income securities at March 31, 2019 , by contractual maturity, are shown in table 7.2 below. Actual maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Because most ABS, RMBS, CMBS, and CLOs provide for periodic payments throughout their lives, they are listed in separate categories. Fixed income securities maturity schedule Table 7.2 March 31, 2019 (In thousands) Amortized cost Fair Value Due in one year or less $ 375,772 $ 375,241 Due after one year through five years 1,748,834 1,753,881 Due after five years through ten years 948,568 966,862 Due after ten years 1,148,093 1,195,465 4,221,267 4,291,449 ABS 217,469 218,481 RMBS 188,201 180,485 CMBS 272,074 269,283 CLOs 330,524 327,662 Total as of March 31, 2019 $ 5,229,535 $ 5,287,360
Cost and fair value of investments in equity securities	The cost and fair value of investments in equity securities at March 31, 2019 and December 31, 2018 are shown in tables 7.3a and 7.3b below. Details of equity security investments as of March 31, 2019 Table 7.3a (In thousands) Cost Gross Gains Gross Losses Fair Value Equity securities $ 4,016 $ 60 $ (19 ) $ 4,057 Details of equity security investments as of December 31, 2018 Table 7.3b (In thousands) Cost Gross Gains Gross Losses Fair Value Equity securities $ 3,993 $ 11 $ (72 ) $ 3,932
Aging of the fair values of securities in an unrealized loss position	Tables 7.4a and 7.4b below summarize, for all available-for-sale investments in an unrealized loss position at March 31, 2019 and December 31, 2018 , the aggregate fair value and gross unrealized loss by the length of time those securities have been continuously in an unrealized loss position. The fair value amounts reported in tables 7.4a and 7.4b are estimated using the process described in Note 8 - “Fair Value Measurements” to these consolidated financial statements and in Note 3 - “Significant Accounting Policies” of the notes to the consolidated financial statements in our 2018 Annual Report on Form 10-K. Unrealized loss aging for securities by type and length of time as of March 31, 2019 Table 7.4a Less Than 12 Months 12 Months or Greater Total (In thousands) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses U.S. Treasury securities and obligations of U.S. government corporations and agencies $ — $ — $ 68,951 $ (589 ) $ 68,951 $ (589 ) Obligations of U.S. states and political subdivisions 17,518 (444 ) 213,567 (1,782 ) 231,085 (2,226 ) Corporate debt securities 149,625 (1,315 ) 852,102 (8,333 ) 1,001,727 (9,648 ) ABS 18,444 (33 ) — — 18,444 (33 ) RMBS — — 175,437 (7,859 ) 175,437 (7,859 ) CMBS 9,757 (94 ) 189,785 (4,505 ) 199,542 (4,599 ) CLOs 317,663 (2,862 ) — — 317,663 (2,862 ) Total $ 513,007 $ (4,748 ) $ 1,499,842 $ (23,068 ) $ 2,012,849 $ (27,816 ) Unrealized loss aging for securities by type and length of time as of December 31, 2018 Table 7.4b Less Than 12 Months 12 Months or Greater Total (In thousands) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 23,710 $ (15 ) $ 69,146 $ (1,061 ) $ 92,856 $ (1,076 ) Obligations of U.S. states and political subdivisions 316,655 (3,875 ) 358,086 (7,110 ) 674,741 (10,985 ) Corporate debt securities 1,272,279 (18,130 ) 785,627 (22,384 ) 2,057,906 (40,514 ) ABS 51,324 (146 ) — — 51,324 (146 ) RMBS 24 — 178,573 (10,309 ) 178,597 (10,309 ) CMBS 65,704 (1,060 ) 163,272 (8,520 ) 228,976 (9,580 ) CLOs 296,497 (5,294 ) — — 296,497 (5,294 ) Total $ 2,026,193 $ (28,520 ) $ 1,554,704 $ (49,384 ) $ 3,580,897 $ (77,904 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair value measurements for items measured at fair value	Assets measured at fair value, by hierarchy level, as of March 31, 2019 and December 31, 2018 are shown in tables 8.1a and 8.1b below. The fair value of the assets is estimated using the process described above, and more fully in Note 3 - “Significant Accounting Policies” of the notes to the consolidated financial statements in our 2018 Annual Report on Form 10-K. Assets carried at fair value by hierarchy level as of March 31, 2019 Table 8.1a (In thousands) Total Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 168,142 $ 42,479 $ 125,663 $ — Obligations of U.S. states and political subdivisions 1,667,238 — 1,667,238 — Corporate debt securities 2,456,069 — 2,456,069 — ABS 218,481 — 218,481 — RMBS 180,485 — 180,485 — CMBS 269,283 — 269,283 — CLOs 327,662 — 327,662 — Total fixed income securities 5,287,360 42,479 5,244,881 — Equity securities 4,057 4,057 — — Other (1) 205,444 205,444 — — Real estate acquired (2) 11,639 — — 11,639 Total $ 5,508,500 $ 251,980 $ 5,244,881 $ 11,639 Assets carried at fair value by hierarchy level as of December 31, 2018 Table 8.1b (In thousands) Total Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 167,176 $ 42,264 $ 124,912 $ — Obligations of U.S. states and political subdivisions 1,720,100 — 1,720,087 13 Corporate debt securities 2,400,762 — 2,400,762 — ABS 112,033 — 112,033 — RMBS 178,961 — 178,961 — CMBS 267,660 — 267,660 — CLOs 305,295 — 305,295 — Total fixed income securities 5,151,987 42,264 5,109,710 13 Equity securities 3,932 3,932 — — Other (1) 96,403 96,403 — — Real estate acquired (2) 14,535 — — 14,535 Total $ 5,266,857 $ 142,599 $ 5,109,710 $ 14,548 (1) Consists of money market funds included in “Cash and Cash Equivalents” and “Restricted Cash and Cash Equivalents” on the consolidated balance sheets. (2) Real estate acquired through claim settlement, which is held for sale, is reported in “Other assets” on the consolidated balance sheets.
Reconciliation of beginning and ending balance for assets and liabilities measured at fair value with significant unobservable inputs (level 3)	For assets measured at fair value using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances for the three months ended March 31, 2019 and 2018 is shown in tables 8.2a and 8.2b below. As shown in table 8.2b below, we transferred our FHLB stock out of Level 3 assets, and it is carried at cost, which approximates fair value, on our consolidated balance sheet in “Other invested assets.” There were no losses included in earnings for those periods attributable to the change in unrealized losses on assets still held at the end of the applicable period. Fair value roll-forward for financial instruments classified as Level 3 for the three months ended March 31, 2019 Table 8.2a (In thousands) Fixed income Equity Securities Total Investments Real Estate Acquired Balance at December 31, 2018 $ 13 $ — $ 13 $ 14,535 Purchases — — — 8,084 Sales (13 ) — (13 ) (10,872 ) Included in earnings and reported as losses incurred, net — — — (108 ) Balance at March 31, 2019 $ — $ — $ — $ 11,639 Fair value roll-forward for financial instruments classified as Level 3 for the three months ended March 31, 2018 Table 8.2b (In thousands) Fixed income Equity Total Real Estate Balance at December 31, 2017 271 4,268 4,539 12,713 Transfers out of Level 3 — (3,100 ) (3,100 ) — Purchases — — — 5,894 Sales (17 ) — (17 ) (8,870 ) Included in earnings and reported as losses incurred, net — — — 341 Balance at March 31, 2018 $ 254 $ 1,168 $ 1,422 $ 10,078
Carrying value and fair value of financial assets and liabilities	Table 8.3 presents the carrying value and fair value of our financial assets and liabilities disclosed, but not carried, at fair value at March 31, 2019 and December 31, 2018 . Financial assets and liabilities not measured at fair value Table 8.3 March 31, 2019 December 31, 2018 (In thousands) Carrying Value Fair Value Carrying Value Fair Value Financial assets Other invested assets $ 3,100 $ 3,100 $ 3,100 $ 3,100 Financial liabilities FHLB Advance $ 155,000 $ 153,133 $ 155,000 $ 150,551 5.75% Senior Notes 420,002 449,387 419,713 425,791 9% Convertible Junior Subordinated Debentures 256,872 332,580 256,872 338,069 Total financial liabilities $ 831,874 $ 935,100 $ 831,585 $ 914,411

Other Comprehensive Income (Tab

Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2019
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Other comprehensive income	The pretax and related income tax (expense) benefit components of our other comprehensive income (loss) for the three months ended March 31, 2019 and 2018 are included in table 9.1 below. Components of other comprehensive income (loss) Table 9.1 Three Months Ended March 31, (In thousands) 2019 2018 Net unrealized investment gains (losses) arising during the period $ 102,621 $ (81,587 ) Income tax (expense) benefit (21,550 ) 17,134 Net of taxes 81,071 (64,453 ) Net changes in benefit plan assets and obligations 2,089 625 Income tax expense (439 ) (131 ) Net of taxes 1,650 494 Total other comprehensive income (loss) 104,710 (80,962 ) Total income tax (expense) benefit (21,989 ) 17,003 Total other comprehensive income (loss), net of tax $ 82,721 $ (63,959 )
Reclassification out of accumulated other comprehensive income	The pretax and related income tax benefit (expense) components of the amounts reclassified from our accumulated other comprehensive loss (“AOCL”) to our consolidated statements of operations for the three months ended March 31, 2019 and 2018 are included in table 9.2 below. Reclassifications from AOCL Table 9.2 Three Months Ended March 31, (In thousands) 2019 2018 Reclassification adjustment for net realized (losses) (1) $ (2,679 ) $ (91 ) Income tax benefit 563 19 Net of taxes (2,116 ) (72 ) Reclassification adjustment related to benefit plan assets and obligations (2) (2,089 ) (625 ) Income tax benefit (expense) 439 131 Net of taxes (1,650 ) (494 ) Total reclassifications (4,768 ) (716 ) Total income tax benefit 1,002 150 Total reclassifications, net of tax $ (3,766 ) $ (566 ) (1) Increases (decreases) Net realized investment (losses) gains on the consolidated statements of operations. (2) Decreases (increases) Other underwriting and operating expenses, net on the consolidated statements of operations.
Accumulated other comprehensive income (loss)	A rollforward of AOCL for the three months ended March 31, 2019 , including amounts reclassified from AOCL, are included in table 9.3 below. Rollforward of AOCL Table 9.3 Three Months Ended March 31, 2019 (In thousands) Net unrealized gains and (losses) on available-for-sale securities Net benefit plan assets and (obligations) recognized in shareholders' equity Total AOCL Balance, December 31, 2018, net of tax $ (35,389 ) $ (88,825 ) $ (124,214 ) Other comprehensive income before reclassifications 78,955 — 78,955 Less: Amounts reclassified from AOCL (2,116 ) (1,650 ) (3,766 ) Balance, March 31, 2019, net of tax $ 45,682 $ (87,175 ) $ (41,493 )

Benefit Plans (Tables)

Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2019
Retirement Benefits [Abstract]
Components of net periodic benefit cost	Table 10.1 provides the components of net periodic benefit cost for our pension, supplemental executive retirement and other postretirement benefit plans for the three months ended March 31, 2019 and 2018 . Components of net periodic benefit cost Table 10.1 Three Months Ended March 31, Pension and Supplemental Executive Retirement Plans Other Postretirement Benefit Plans (In thousands) 2019 2018 2019 2018 Service cost $ 1,996 $ 2,562 $ 312 $ 270 Interest cost 3,955 3,782 291 214 Expected return on plan assets (4,908 ) (5,570 ) (1,445 ) (1,588 ) Amortization of net actuarial losses/(gains) 2,167 1,785 — (46 ) Amortization of prior service cost/(credit) (70 ) (87 ) (8 ) (1,026 ) Net periodic benefit cost (benefit) $ 3,140 $ 2,472 $ (850 ) $ (2,176 )

Loss Reserves (Tables)

Loss Reserves (Tables)	3 Months Ended
	Mar. 31, 2019
Insurance Loss Reserves [Abstract]
Reconciliation of beginning and ending loss reserves	Table 11.1 provides a reconciliation of beginning and ending loss reserves as of and for the three months ended March 31, 2019 and 2018 . Development of reserves for losses and loss adjustment expenses Table 11.1 Three Months Ended March 31, (In thousands) 2019 2018 Reserve at beginning of period $ 674,019 $ 985,635 Less reinsurance recoverable 33,328 48,474 Net reserve at beginning of period 640,691 937,161 Losses incurred: Losses and LAE incurred in respect of delinquency notices received in: Current year 47,488 59,070 Prior years (1) (8,425 ) (35,220 ) Total losses incurred 39,063 23,850 Losses paid: Losses and LAE paid in respect of delinquency notices received in: Current year — 95 Prior years 56,365 81,983 Reinsurance terminations — 236 Total losses paid 56,365 82,314 Net reserve at end of period 623,389 878,697 Plus reinsurance recoverables 31,875 45,474 Reserve at end of period $ 655,264 $ 924,171 (1) A negative number for prior year losses incurred indicates a redundancy of prior year loss reserves. See the following table for more information about prior year loss development.
Prior year development of the reserves	The prior year development of the reserves in the first three months of 2019 and 2018 is reflected in table 11.2 below. Reserve development on previously received delinquencies Table 11.2 Three Months Ended March 31, (In millions) 2019 2018 Decrease in estimated claim rate on primary defaults $ (31 ) $ (47 ) Increase in estimated severity on primary defaults — 16 Change in estimates related to pool reserves, LAE reserves, reinsurance, and other 23 (4 ) Total prior year loss development (1) $ (8 ) $ (35 ) (1) A negative number for prior year loss development indicates a redundancy of prior year loss reserves.
Rollforward of primary delinquent inventory	A rollforward of our primary delinquent inventory for the three months ended March 31, 2019 and 2018 appears in table 11.3 below. The information concerning new notices and cures is compiled from monthly reports received from loan servicers. The level of new notice and cure activity reported in a particular month can be influenced by, among other things, the date on which a servicer generates its report, the accuracy of the data provided by servicers, the number of business days in a month, transfers of servicing between loan servicers and whether all servicers have provided the reports in a given month. Delinquent inventory rollforward Table 11.3 Three Months Ended March 31, 2019 2018 Delinquent inventory at beginning of period 32,898 46,556 New notices 13,611 14,623 Cures (14,348 ) (18,073 ) Paid claims (1,188 ) (1,571 ) Rescissions and denials (52 ) (68 ) Other items removed from inventory — (224 ) Delinquent inventory at end of period 30,921 41,243
Aging of the primary delinquent inventory	Table 11.4 below shows the number of consecutive months a borrower is delinquent. Primary delinquent inventory - consecutive months delinquent Table 11.4 March 31, 2019 December 31, 2018 March 31, 2018 3 months or less 8,568 9,829 8,770 4-11 months 9,997 9,655 16,429 12 months or more (1) 12,356 13,414 16,044 Total 30,921 32,898 41,243 3 months or less 28 % 30 % 21 % 4-11 months 32 % 29 % 40 % 12 months or more 40 % 41 % 39 % Total 100 % 100 % 100 % Primary claims received inventory included in ending delinquent inventory: 665 809 819 (1) Approximately 38% , 38% , and 44% of the primary delinquent inventory delinquent for 12 consecutive months or more has been delinquent for at least 36 consecutive months as of March 31, 2019 , December 31, 2018 , and March 31, 2018 , respectively.

Share-Based Compensation (Table

Share-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of stock-based compensation, activity	Table 13.1 shows the number of shares granted to employees and the weighted average fair value per share during the periods presented (shares in thousands). Restricted stock grants Table 13.1 Three Months Ended March 31, 2019 2018 Shares Granted Weighted Average Share Fair Value Shares Granted Weighted Average Share Fair Value RSUs subject to performance conditions 1,378 $ 11.76 1,239 $ 15.80 RSUs subject only to service conditions 412 11.76 412 15.71

Significant Accounting Polici_4

Significant Accounting Policies Significant Accounting Policies (Details) $ in Millions	Mar. 31, 2019USD ($)
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Minimum future operating lease payments	$ 2.6

Debt - Summary of Debt Obligati

Debt - Summary of Debt Obligations (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt, carrying value	$ 831,900,000	$ 831,600,000
Federal Home Loan Bank Advances (FHLB)
Debt Instrument [Line Items]
Long-term debt, carrying value	$ 155,000,000	155,000,000
Stated interest rate	1.91%
Senior Notes | 5.75% Senior Notes Due 2023
Debt Instrument [Line Items]
Long-term debt, carrying value	$ 420,000,000	419,700,000
Stated interest rate	5.75%
Debt instrument, face amount	$ 425,000,000
9% Convertible Junior Subordinated Debentures
Debt Instrument [Line Items]
Long-term debt, carrying value	$ 256,900,000	$ 256,900,000
Stated interest rate	9.00%

Debt - Narrative (Details)

Debt - Narrative (Details)	3 Months Ended
	Mar. 31, 2019USD ($)$ / shares	Mar. 31, 2018USD ($)
Debt Instrument [Line Items]
Total interest payments	$ 13,100,000	$ 13,100,000
9% Convertible Junior Subordinated Debentures
Debt Instrument [Line Items]
Conversion rate (in shares per $1,000 note)	0.0740741
Principal amount of notes used in determining conversion rate	$ 1,000
Convertible debt, conversion price (in dollars per share) | $ / shares	$ 13.50
Period preceding election to convert (in days)	5 days
Stated interest rate	9.00%
Senior Notes | 5.75% Senior Notes Due 2023
Debt Instrument [Line Items]
Stated interest rate	5.75%

Reinsurance - Summary of Premiu

Reinsurance - Summary of Premiums Earned and Losses Incurred (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Premiums earned:
Direct	$ 279,613	$ 265,251
Assumed	872	121
Ceded	(30,724)	(33,265)
Net premiums earned	249,761	232,107
Losses incurred:
Direct	40,804	31,501
Assumed	(67)	90
Ceded	(1,674)	(7,741)
Losses incurred, net	$ 39,063	$ 23,850

Reinsurance - Narrative (Detail

Reinsurance - Narrative (Details) - USD ($)	Jun. 30, 2019	Mar. 31, 2019	Mar. 31, 2018
Effects of Reinsurance [Line Items]
Ceded premiums		$ 30,724,000	$ 33,265,000
Prior years		56,365,000	$ 81,983,000
Quota Share Reinsurance Agreement, 2019
Effects of Reinsurance [Line Items]
Contingent termination fee		$ 0
Threshold for private mortgage insurer eligibility requirements for termination election (less than) (as a percent)		90.00%
Quota share for all policies covered (as a percent)		30.00%
Cede rate, option 1 (as a percent)		25.00%
Cede rate, option 2 (as a percent)		20.00%
Ceding commission, percentage (as a percent)		20.00%
Loss ratio threshold for profit commissions (as a percent)		62.00%
Quota Share Reinsurance Agreement, 2015
Effects of Reinsurance [Line Items]
Quota share for all policies covered (as a percent)		30.00%
Quota Share Reinsurance Agreement, 2015 | Forecast
Effects of Reinsurance [Line Items]
Quota share for all policies covered (as a percent)	15.00%
Loss ratio threshold for profit commissions (as a percent)	68.00%
Excess of Loss Reinsurance Agreement, Home Re
Effects of Reinsurance [Line Items]
Ceded premiums		$ 2,500,000

Reinsurance - Summary of Quota

Reinsurance - Summary of Quota Reinsurance Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Effects of Reinsurance [Line Items]
Ceded losses incurred	$ 1,674	$ 7,741
Reinsurance recoverable on loss reserves	31,875	45,474	$ 33,328	$ 48,474
Quota Share Reinsurance Agreements, Excluding Captive Agreements
Effects of Reinsurance [Line Items]
Ceded premiums written and earned, net of profit commission	28,164	33,036
Ceded losses incurred	1,676	7,788
Ceding commissions	13,409	12,645
Profit commission	38,881	$ 30,189
Reinsurance recoverable on loss reserves	$ 31,800		$ 33,200

Reinsurance Reinsurance - Varia

Reinsurance Reinsurance - Variable Interest Entity (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Home Re
Effects of Reinsurance [Line Items]
Total VIE Assets	$ 318,636	$ 318,636

Litigation and Contingencies (D

Litigation and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Average paid claim reduction due to curtailments (as a percent)	3.90%	5.80%
Probable loss contingency accrual	$ 23.5
Maximum exposure associated with other discussions and legal proceedings	$ 266.2

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Basic earnings per share:
Net income	$ 151,941	$ 143,637
Weighted average common shares outstanding - basic (in shares)	355,653	370,908
Basic earnings per share (in dollars per share)	$ 0.43	$ 0.39
Diluted earnings per share:
Net income	$ 151,941	$ 143,637
Diluted income available to common shareholders	$ 156,507	$ 148,203
Weighted average common shares outstanding - basic (in shares)	355,653	370,908
Effect of dilutive securities:
Weighted average common shares outstanding - diluted (in shares)	376,667	391,562
Diluted earnings per share (in dollars per share)	$ 0.42	$ 0.38
Effective income tax rate	21.00%	21.00%
9% Convertible Junior Subordinated Debentures
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stated interest rate	9.00%
Diluted earnings per share:
Dilutive securities	$ 4,566	$ 4,566
Effect of dilutive securities:
Dilutive securities (in shares)	19,028	19,028
Unvested RSUs
Effect of dilutive securities:
Unvested RSUs (in shares)	1,986	1,626

Investments (Details)

Investments (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2019USD ($)security	Mar. 31, 2018USD ($)	Dec. 31, 2018USD ($)security
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 5,229,535,000		$ 5,196,784,000
Fair Value	5,287,360,000		5,151,987,000
Other-than-temporary impairment losses	0		0
Assets held by insurance regulators	13,600,000		$ 13,500,000
Proceeds from sales of fixed income securities	106,000,000	$ 10,800,000
Gross realized gains, fixed income securities	700,000	100,000
Net impairment losses recognized in earnings	$ 100,000	0
Federal Home Loan Bank advances, collateral, value of principal, percent (as a percent)	102.00%
FHLB advance collateral	$ 171,600,000
Number of securities in unrealized loss position (in securities) | security	420		721
Total fixed income securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 5,229,535,000		$ 5,196,784,000
Gross Unrealized Gains	85,641,000		33,107,000
Gross Unrealized Losses	(27,816,000)		(77,904,000)
Fair Value	5,287,360,000		5,151,987,000
Gross realized gain, fixed income securities	1,300,000	$ 300,000
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	167,821,000		167,655,000
Gross Unrealized Gains	910,000		597,000
Gross Unrealized Losses	(589,000)		(1,076,000)
Fair Value	168,142,000		167,176,000
Obligations of U.S. states and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,611,092,000		1,701,826,000
Gross Unrealized Gains	58,372,000		29,259,000
Gross Unrealized Losses	(2,226,000)		(10,985,000)
Fair Value	1,667,238,000		1,720,100,000
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,442,354,000		2,439,173,000
Gross Unrealized Gains	23,363,000		2,103,000
Gross Unrealized Losses	(9,648,000)		(40,514,000)
Fair Value	2,456,069,000		2,400,762,000
Asset backed securities (“ABS”)
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	217,469,000		111,953,000
Gross Unrealized Gains	1,045,000		226,000
Gross Unrealized Losses	(33,000)		(146,000)
Fair Value	218,481,000		112,033,000
Residential mortgage backed securities (“RMBS”)
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	188,201,000		189,238,000
Gross Unrealized Gains	143,000		32,000
Gross Unrealized Losses	(7,859,000)		(10,309,000)
Fair Value	180,485,000		178,961,000
Commercial mortgage backed securities (“CMBS”)
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	272,074,000		276,352,000
Gross Unrealized Gains	1,808,000		888,000
Gross Unrealized Losses	(4,599,000)		(9,580,000)
Fair Value	269,283,000		267,660,000
Collateralized loan obligations (“CLO”)
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	330,524,000		310,587,000
Gross Unrealized Gains	0		2,000
Gross Unrealized Losses	(2,862,000)		(5,294,000)
Fair Value	$ 327,662,000		$ 305,295,000

Investments - Amortized Cost an

Investments - Amortized Cost and Fair Values of Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Amortized cost
Due in one year or less	$ 375,772
Due after one year through five years	1,748,834
Due after five years through ten years	948,568
Due after ten years	1,148,093
Total debt securities with single maturity date, amortized cost	4,221,267
Amortized Cost	5,229,535	$ 5,196,784
Fair Value
Due in one year or less	375,241
Due after one year through five years	1,753,881
Due after five years through ten years	966,862
Due after ten years	1,195,465
Total debt securities with single maturity date, fair value	4,291,449
Total at end of period	5,287,360	5,151,987
Asset backed securities (“ABS”)
Amortized cost
Total debt securities without single maturity date, amortized cost	217,469
Amortized Cost	217,469	111,953
Fair Value
Total debt securities without single maturity date, fair value	218,481
Total at end of period	218,481	112,033
Residential mortgage backed securities (“RMBS”)
Amortized cost
Total debt securities without single maturity date, amortized cost	188,201
Amortized Cost	188,201	189,238
Fair Value
Total debt securities without single maturity date, fair value	180,485
Total at end of period	180,485	178,961
Commercial mortgage backed securities (“CMBS”)
Amortized cost
Total debt securities without single maturity date, amortized cost	272,074
Amortized Cost	272,074	276,352
Fair Value
Total debt securities without single maturity date, fair value	269,283
Total at end of period	269,283	267,660
Collateralized loan obligations (“CLO”)
Amortized cost
Total debt securities without single maturity date, amortized cost	330,524
Amortized Cost	330,524	310,587
Fair Value
Total debt securities without single maturity date, fair value	327,662
Total at end of period	$ 327,662	$ 305,295

Investments - Equity Securities

Investments - Equity Securities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Equity Securities, FV-NI, Gain (Loss) [Abstract]
Cost	$ 4,016		$ 3,993
Gross Gains	60		11
Gross Losses	(19)		(72)
Fair Value	4,057		$ 3,932
Unrealized Gain (Loss) on Equity Securities [Abstract]
Recognized net gains (losses) on equity securities still held	$ 100	$ (100)

Investments - Securities In Unr

Investments - Securities In Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months	$ 513,007	$ 2,026,193
12 Months or Greater	1,499,842	1,554,704
Total	2,012,849	3,580,897
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Reportable Items [Abstract]
Less Than 12 Months	(4,748)	(28,520)
12 Months or Greater	(23,068)	(49,384)
Total	(27,816)	(77,904)
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months	0	23,710
12 Months or Greater	68,951	69,146
Total	68,951	92,856
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Reportable Items [Abstract]
Less Than 12 Months	0	(15)
12 Months or Greater	(589)	(1,061)
Total	(589)	(1,076)
Obligations of U.S. states and political subdivisions
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months	17,518	316,655
12 Months or Greater	213,567	358,086
Total	231,085	674,741
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Reportable Items [Abstract]
Less Than 12 Months	(444)	(3,875)
12 Months or Greater	(1,782)	(7,110)
Total	(2,226)	(10,985)
Corporate debt securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months	149,625	1,272,279
12 Months or Greater	852,102	785,627
Total	1,001,727	2,057,906
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Reportable Items [Abstract]
Less Than 12 Months	(1,315)	(18,130)
12 Months or Greater	(8,333)	(22,384)
Total	(9,648)	(40,514)
Asset backed securities (“ABS”)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months	18,444	51,324
12 Months or Greater	0	0
Total	18,444	51,324
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Reportable Items [Abstract]
Less Than 12 Months	(33)	(146)
12 Months or Greater	0	0
Total	(33)	(146)
Residential mortgage backed securities (“RMBS”)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months	0	24
12 Months or Greater	175,437	178,573
Total	175,437	178,597
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Reportable Items [Abstract]
Less Than 12 Months	0	0
12 Months or Greater	(7,859)	(10,309)
Total	(7,859)	(10,309)
Commercial mortgage backed securities (“CMBS”)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months	9,757	65,704
12 Months or Greater	189,785	163,272
Total	199,542	228,976
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Reportable Items [Abstract]
Less Than 12 Months	(94)	(1,060)
12 Months or Greater	(4,505)	(8,520)
Total	(4,599)	(9,580)
Collateralized loan obligations (“CLO”)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months	317,663	296,497
12 Months or Greater	0	0
Total	317,663	296,497
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Reportable Items [Abstract]
Less Than 12 Months	(2,862)	(5,294)
12 Months or Greater	0	0
Total	$ (2,862)	$ (5,294)

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	$ 5,287,360	$ 5,151,987
Equity securities, at fair value (cost 2019 - $4,016; 2018 - $3,993)	4,057	3,932
Other	205,444	96,403
Real estate acquired	11,639	14,535
Total assets	5,508,500	5,266,857
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other	205,444	96,403
Real estate acquired	0	0
Total assets	251,980	142,599
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other	0	0
Real estate acquired	0	0
Total assets	5,244,881	5,109,710
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other	0	0
Real estate acquired	11,639	14,535
Total assets	11,639	14,548
Total fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	5,287,360	5,151,987
Total fixed income securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	42,479	42,264
Total fixed income securities | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	5,244,881	5,109,710
Total fixed income securities | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	13
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	168,142	167,176
U.S. Treasury securities and obligations of U.S. government corporations and agencies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	42,479	42,264
U.S. Treasury securities and obligations of U.S. government corporations and agencies | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	125,663	124,912
U.S. Treasury securities and obligations of U.S. government corporations and agencies | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Obligations of U.S. states and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	1,667,238	1,720,100
Obligations of U.S. states and political subdivisions | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Obligations of U.S. states and political subdivisions | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	1,667,238	1,720,087
Obligations of U.S. states and political subdivisions | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	13
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	2,456,069	2,400,762
Corporate debt securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Corporate debt securities | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	2,456,069	2,400,762
Corporate debt securities | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Asset backed securities (“ABS”)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	218,481	112,033
Asset backed securities (“ABS”) | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Asset backed securities (“ABS”) | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	218,481	112,033
Asset backed securities (“ABS”) | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Residential mortgage backed securities (“RMBS”)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	180,485	178,961
Residential mortgage backed securities (“RMBS”) | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Residential mortgage backed securities (“RMBS”) | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	180,485	178,961
Residential mortgage backed securities (“RMBS”) | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Commercial mortgage backed securities (“CMBS”)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	269,283	267,660
Commercial mortgage backed securities (“CMBS”) | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Commercial mortgage backed securities (“CMBS”) | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	269,283	267,660
Commercial mortgage backed securities (“CMBS”) | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Collateralized loan obligations (“CLO”)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	327,662	305,295
Collateralized loan obligations (“CLO”) | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Collateralized loan obligations (“CLO”) | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	327,662	305,295
Collateralized loan obligations (“CLO”) | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed income, available-for-sale, at fair value (amortized cost 2019 - $5,229,535; 2018 - $5,196,784)	0	0
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value (cost 2019 - $4,016; 2018 - $3,993)	4,057	3,932
Equity securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value (cost 2019 - $4,016; 2018 - $3,993)	4,057	3,932
Equity securities | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value (cost 2019 - $4,016; 2018 - $3,993)	0	0
Equity securities | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, at fair value (cost 2019 - $4,016; 2018 - $3,993)	$ 0	$ 0

Fair Value Measurements - Unobs

Fair Value Measurements - Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Total Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 13	$ 4,539
Transfers out of Level 3		(3,100)
Purchases	0	0
Sales	(13)	(17)
Included in earnings and reported as losses incurred, net	0	0
Balance at end of period	0	1,422
Fixed income
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	13	271
Transfers out of Level 3		0
Purchases	0	0
Sales	(13)	(17)
Included in earnings and reported as losses incurred, net	0	0
Balance at end of period	0	254
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	0	4,268
Transfers out of Level 3		(3,100)
Purchases	0	0
Sales	0	0
Included in earnings and reported as losses incurred, net	0	0
Balance at end of period	0	1,168
Real Estate Acquired
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	14,535	12,713
Transfers out of Level 3		0
Purchases	8,084	5,894
Sales	(10,872)	(8,870)
Included in earnings and reported as losses incurred, net	(108)	341
Balance at end of period	$ 11,639	$ 10,078

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Not Measured at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other invested assets	$ 3,100	$ 3,100
FHLB Advance	155,000	155,000
5.75% Senior Notes	420,002	419,713
9% Convertible Junior Subordinated Debentures	256,872	256,872
Total financial liabilities	831,874	831,585
Fair Value | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other invested assets	3,100	3,100
FHLB Advance	153,133	150,551
5.75% Senior Notes	449,387	425,791
9% Convertible Junior Subordinated Debentures	332,580	338,069
Total financial liabilities	$ 935,100	$ 914,411
Senior Notes | 5.75% Senior Notes Due 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate	5.75%
9% Convertible Junior Subordinated Debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate	9.00%

Other Comprehensive Income (Det

Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total other comprehensive income (loss)	$ 104,710	$ (80,962)
Income tax (expense) benefit	(21,989)	17,003
Other comprehensive income (loss), net of tax	82,721	(63,959)
Amounts Reclassified From Accumulated Other Comprehensive Income [Abstract]
Income before tax	190,936	180,025
Income tax benefit (expense)	(38,995)	(36,388)
Net income	151,941	143,637
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	3,581,891
Other comprehensive income before reclassifications	78,955
Less: Amounts reclassified from AOCL	(3,766)
Balance, end of period	3,816,183	3,231,403
Reclassification from Accumulated Other Comprehensive Income
Amounts Reclassified From Accumulated Other Comprehensive Income [Abstract]
Income before tax	(4,768)	(716)
Income tax benefit (expense)	1,002	150
Net income	(3,766)	(566)
Accumulated other comprehensive (loss) income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive income (loss), net of tax	82,721	(63,959)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(124,214)	(43,801)
Balance, end of period	(41,493)	(107,760)
Net unrealized gains and (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total other comprehensive income (loss)	102,621	(81,587)
Income tax (expense) benefit	(21,550)	17,134
Other comprehensive income (loss), net of tax	81,071	(64,453)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(35,389)
Other comprehensive income before reclassifications	78,955
Less: Amounts reclassified from AOCL	(2,116)
Balance, end of period	45,682
Net unrealized gains and (losses) on available-for-sale securities | Reclassification from Accumulated Other Comprehensive Income
Amounts Reclassified From Accumulated Other Comprehensive Income [Abstract]
Income before tax	(2,679)	(91)
Income tax benefit (expense)	563	19
Net income	(2,116)	(72)
Net benefit plan assets and (obligations) recognized in shareholders' equity
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total other comprehensive income (loss)	2,089	625
Income tax (expense) benefit	(439)	(131)
Other comprehensive income (loss), net of tax	1,650	494
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(88,825)
Other comprehensive income before reclassifications	0
Less: Amounts reclassified from AOCL	(1,650)
Balance, end of period	(87,175)
Net benefit plan assets and (obligations) recognized in shareholders' equity | Reclassification from Accumulated Other Comprehensive Income
Amounts Reclassified From Accumulated Other Comprehensive Income [Abstract]
Income before tax	(2,089)	(625)
Income tax benefit (expense)	439	131
Net income	$ (1,650)	$ (494)

Benefit Plans (Details)

Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Pension and Supplemental Executive Retirement Plans
Components of Net Periodic Benefit Cost [Abstract]
Service cost	$ 1,996	$ 2,562
Interest cost	3,955	3,782
Expected return on plan assets	(4,908)	(5,570)
Amortization of net actuarial losses/(gains)	2,167	1,785
Amortization of prior service cost/(credit)	(70)	(87)
Net periodic benefit cost (benefit)	3,140	2,472
Estimated future employer contributions in current fiscal year	10,700
Other Postretirement Benefit Plans
Components of Net Periodic Benefit Cost [Abstract]
Service cost	312	270
Interest cost	291	214
Expected return on plan assets	(1,445)	(1,588)
Amortization of net actuarial losses/(gains)	0	(46)
Amortization of prior service cost/(credit)	(8)	(1,026)
Net periodic benefit cost (benefit)	$ (850)	$ (2,176)

Loss Reserves (Details)

Loss Reserves (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019USD ($)loan	Mar. 31, 2018USD ($)loan	Dec. 31, 2018USD ($)
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Percentage of prior year delinquent inventory resolved (as a percent)	32.00%	31.00%
Prior years	$ (8,425)	$ (35,220)
Claims paid upon commutation of coverage of pools	56,365	$ 81,983
Premium refund liability, expected claim payments	$ 37,000		$ 40,000
Primary Delinquent Inventory [Roll Forward]
Delinquent inventory at the beginning of period (in loans) | loan	32,898	46,556
New notices (in loans) | loan	13,611	14,623
Cures (in loans) | loan	(14,348)	(18,073)
Paids (including those charged to a deductible or captive) (in loans) | loan	(1,188)	(1,571)
Rescissions and denials (in loans) | loan	(52)	(68)
Other items removed from inventory (in loans) | loan	0	(224)
Delinquent inventory at end of period (in loans) | loan	30,921	41,243
Probable loss on litigation claims paying practices
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Prior years	$ 23,500
Settlements for commutations of coverage, pools of nonperforming loans
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Claims paid upon commutation of coverage of pools		$ 7,000
Decrease in estimated claim rate on primary defaults
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Prior years	(31,000)	(47,000)
Increase in estimated severity on primary defaults
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Prior years	0	16,000
Change in estimates related to pool reserves, LAE reserves, reinsurance, and other
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Prior years	$ 23,000	$ (4,000)

Loss Reserves - Reconciliation

Loss Reserves - Reconciliation of Beginning and Ending Balances (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Loss Reserve [Roll Forward]
Reserve at beginning of period	$ 674,019	$ 985,635
Less reinsurance recoverable	33,328	48,474
Net reserve at beginning of period	640,691	937,161
Losses and LAE incurred in respect of delinquency notices received in:
Current year	47,488	59,070
Prior years	(8,425)	(35,220)
Total losses incurred	39,063	23,850
Losses and LAE paid in respect of delinquency notices received in:
Current year	0	95
Prior years	56,365	81,983
Reinsurance terminations	0	236
Total losses paid	56,365	82,314
Net reserve at end of period	623,389	878,697
Plus reinsurance recoverables	31,875	45,474
Reserve at end of period	$ 655,264	$ 924,171

Loss Reserves - Delinquent Item

Loss Reserves - Delinquent Items (Details) - loan	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Aging of the Primary Delinquent Inventory [Abstract]
3 months or less (in loans)	8,568	9,829	8,770
3 months or less (as a percent)	28.00%	30.00%	21.00%
4 - 11 months (in loans)	9,997	9,655	16,429
4 - 11 months (as a percent)	32.00%	29.00%	40.00%
12 months or more (in loans)	12,356	13,414	16,044
12 months or more (as a percent)	40.00%	41.00%	39.00%
Total primary delinquent inventory (in loans)	30,921	32,898	41,243	46,556
Total primary delinquent inventory (as a percent)	100.00%	100.00%	100.00%
Primary claims received inventory included in ending delinquent inventory (in loans)	665	809	819
Percent of 12 months or more delinquent inventory, delinquent for more than 36 months (as a percent)	38.00%	38.00%	44.00%
Pool insurance delinquent inventory (in loans)	723	859	1,200

Shareholders' Equity (Details)

Shareholders' Equity (Details) $ in Millions	Mar. 31, 2019USD ($)
First Quarter 2019 Repurchase Program
Class of Stock [Line Items]
Authorized repurchase amount	$ 200
Second Quarter 2018 Repurchase Program
Class of Stock [Line Items]
Remaining authorized repurchase amount	$ 25

Share-Based Compensation (Detai

Share-Based Compensation (Details) - $ / shares shares in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
RSUs subject to performance conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	1,378	1,239
Weighted Average Share Fair Value (in dollars per share)	$ 11.76	$ 15.80
RSUs subject only to service conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	412	412
Weighted Average Share Fair Value (in dollars per share)	$ 11.76	$ 15.71
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	1 year
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years

Statutory Information (Details)

Statutory Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)jurisdiction
Statutory capital requirements [Abstract]
Number of jurisdictions with risk-to-capital requirements (in jurisdictions) | jurisdiction	16
Maximum permitted risk-to-capital ratio commonly applied	25 to 1
Risk to capital ratio of combined insurance operations, including reinsurance affiliates, at end of period	9.6 to 1
Risk-to-capital ratio for combined insurance operations	9.6
Percentage of statutory policyholders surplus used to determine maximum allowable dividends (as a percent)	10.00%
Mortgage Guaranty Insurance Corporation
Statutory capital requirements [Abstract]
Maximum risk-to-capital ratio	25
Risk to capital ratio at end of period	8.9 to 1
Risk-to-capital ratio	8.9
Amount of policyholders position above or below required MPP	$ 2,700
Amount of required MPP	1,300
Dividends paid to the parent company	$ 70
Adjusted statutory net income measurement period (in years)	3 years
Adjusted statutory net income dividend payment measurement period (in years)	2 years