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v3.20.2

Current Fair Value of Debt (Parenthetical) (Detail) - USD ($) $ in Thousands |  |  | 1 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Apr. 25, 2018 | Mar. 23, 2017 | Aug. 31, 2020 | Sep. 30, 2020 | Dec. 31, 2019
7.75% Subordinated Notes due 2045 |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Subordinated Notes percentage |  |  | 7.75% | 7.75% | 7.75%
Subordinated Notes due date | 2045 |  | 2045 | 2045 | 2045
Unamortized Debt Issuance Costs |  |  |  |  | $ 3,136
Write off of debt issuance costs |  |  | $ 3,100 |  |
7.875% Subordinated Notes due 2047 |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Subordinated Notes percentage |  |  |  | 7.875% | 7.875%
Subordinated Notes due date | 2047 | 2047 |  | 2047 | 2047
Unamortized Debt Issuance Costs |  |  |  | $ 3,747 | $ 3,853

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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=120391452&loc=d3e13212-122682 + Details
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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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