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Reinsurance - Narrative (Details) - USD ($) |  | 3 Months Ended
--- | --- | ---
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 |

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- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Contingent Termination Fee + References No definition available. + Details
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- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Quota Share, Percent + References No definition available. + Details
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- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Threshold For Private Mortgage Insurer Eligibility Requirements For Termination Election + References No definition available. + Details
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- Definition Amount of earned premiums ceded to other entities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.1) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (b),(c)(2) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84167274&loc=d3e27175-158546 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount, after effects of reinsurance, of payments to settle claims incurred in prior periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65670824&loc=d3e14764-158437 + Details
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