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SCHEDULE II - CONDENSED FINANCIAL INFORMATION OF REGISTRANT - SUPPLEMENTARY NOTES (Details) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Feb. 29, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Supplementary Insurance Information, by Segment [Line Items] |  |  |  |
Percentage of statutory policyholders surplus used to determine maximum allowable dividends |  | 10.00% |  |
Convertible junior subordinated debentures |  | $ 256,872,000 | $ 256,872,000 |
Other Insurance Subsidiaries |  |  |  |
Supplementary Insurance Information, by Segment [Line Items] |  |  |  |
Dividends paid to the parent company |  |  |  | $ 6,500,000
Distributions from other insurance subsidiaries to the parent company |  | 0 | 52,001,000 | 38,500,000
Proceeds from contribution from parent |  | 0 |  | 0
Parent Company |  |  |  |
Supplementary Insurance Information, by Segment [Line Items] |  |  |  |
Convertible junior subordinated debentures |  | $ 389,522,000 | 389,522,000 |
Mortgage Guaranty Insurance Corporation |  |  |  |
Supplementary Insurance Information, by Segment [Line Items] |  |  |  |
Adjusted statutory net income measurement period |  | 3 years |  |
Adjusted statutory net income dividend payment measurement period |  | 2 years |  |
Dividends paid to the parent company |  | $ 140,000,000 | 64,000,000 | 0
Additions to the surplus of MGIC from parent company funds |  | $ 0 | $ 36,025,000 | $ 0
Convertible Junior Subordinated Debentures, at 9% per annum, Due 2063 |  |  |  |
Supplementary Insurance Information, by Segment [Line Items] |  |  |  |
Stated interest rate (in hundredths) |  | 9.00% |  |
Extinguishment of debt, amount | $ 132,700,000 |  |  |

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- Definition The percentage of statutory policyholders' surplus, as defined, as of the preceding calendar year end which is used in the determination of the maximum allowable dividends that the insurance subsidiaries may pay in any twelve-month period without regulatory approval by the Office of the Commissioner of Insurance of the State of Wisconsin. + References No definition available. + Details
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- Definition Statutory Accounting Practices, Statutory Amount Available For Dividend Payments Without Regulatory Approval, Measurement, Measurement Period + References No definition available. + Details
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- Definition Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval, Measurement, Dividend Payment Period + References No definition available. + Details
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- Definition This element represents disclosure of the total aggregate cash dividends paid to the entity by consolidated subsidiaries, by unconsolidated subsidiaries, and by 50% or less owned persons accounted for using the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(b)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.9-06) -URI http://asc.fasb.org/extlink&oid=6882215&loc=d3e537971-122884 + Details
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- Definition Including the current and noncurrent portions, the carrying value of convertible subordinated debt, as of the balance sheet date, initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. This form of debt can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder, and places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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