XML 49 R37.htm IDEA: XBRL DOCUMENT
v3.25.1

Investments - Schedule of available for sale securities (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Dec. 31, 2024
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | $ 216,882,931 | $ 202,308,158
Debt instrument, collateral amount | 4,885,000 | 5,308,000
Investments, fair value disclosure | 10,102,000 | 10,130,000
U.S. Treasury securities and obligations of U.S. government corporations and agencies |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 4,991,733 | 0
Gross Unrealized Gains | 17 | 0
Gross unrealized losses - less than 12 months | 0 | 0
Gross unrealized loss - more than 12 months | 0 | 0
Estimated Fair Value | 4,991,750 | 0
Net Unrealized Losses | 17 | 0
Political subdivisions of States, Territories and Possessions |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 24,267,119 | 24,271,177
Gross Unrealized Gains | 62,010 | 0
Gross unrealized losses - less than 12 months | 0 | (73,589)
Gross unrealized loss - more than 12 months | (2,945,087) | (3,324,491)
Estimated Fair Value | 21,384,042 | 20,873,097
Net Unrealized Losses | (2,883,077) | (3,398,080)
Corporate and other bonds industrial and miscellaneous |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 109,603,106 | 112,507,436
Gross Unrealized Gains | 22,136 | 0
Gross unrealized losses - less than 12 months | (495,587) | (1,024,461)
Gross unrealized loss - more than 12 months | (3,992,684) | (4,690,597)
Estimated Fair Value | 105,136,971 | 106,792,378
Net Unrealized Losses | (4,466,135) | (5,715,058)
Residential mortgage and other asset backed securities |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 78,020,973 | 65,529,545
Gross Unrealized Gains | 300,333 | 119,647
Gross unrealized losses - less than 12 months | (17,773) | (209,890)
Gross unrealized loss - more than 12 months | (5,533,927) | (6,211,339)
Estimated Fair Value | 72,769,606 | 59,227,963
Net Unrealized Losses | (5,251,367) | (6,301,582)
Total fixed-maturity securities |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 216,882,931 | 202,308,158
Gross Unrealized Gains | 384,496 | 119,647
Gross unrealized losses - less than 12 months | (513,360) | (1,307,940)
Gross unrealized loss - more than 12 months | (12,471,698) | (14,226,427)
Estimated Fair Value | 204,282,369 | 186,893,438
Net Unrealized Losses | $ (12,600,562) | $ (15,414,720)

X
- Definition Gross unrealized loss - more than 12 months + References No definition available. + Details
Name: | king_AvailableForSaleSecuritiesContinuousGrossUnrealizedLossPosition12MonthsOrLongerLosses
Namespace Prefix: | king_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Gross unrealized losses - less than 12 months + References No definition available. + Details
Name: | king_AvailableForSaleSecuritiesContinuousGrossUnrealizedLossPositionLessThan12MonthsLosses
Namespace Prefix: | king_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Estimated fair value + References No definition available. + Details
Name: | king_AvailableForSaleSecuritiesFairValueDisclosure1
Namespace Prefix: | king_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Net unrealized gains + References No definition available. + Details
Name: | king_NetUnrealizedGainsLosses
Namespace Prefix: | king_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479130/326-30-45-1 + Details
Name: | us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of unrealized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
Name: | us-gaap_AvailableForSaleDebtSecuritiesGrossUnrealizedGain
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of assets pledged to secure a debt instrument. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477734/942-470-50-3 + Details
Name: | us-gaap_DebtInstrumentCollateralAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2E -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_InvestmentsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 + Details
Name: | us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=king_USTreasurySecuritiesAndObligationsUSGovernmentCorporationsAndAgenciesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=king_FixedMaturitySecuritiesPoliticalSubdivisionsOfStatesTerritoriesAndPossessionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=king_FixedMaturitySecuritiesCorporateAndOtherBondsIndustrialAndMiscellaneousMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=king_FixedMaturitySecuritiesMortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=king_FixedMaturitySecuritiesTotalFixedMaturitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |