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v3.21.2

Debt - Additional Information (Detail) - USD ($) |  |  | 6 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 23, 2018 | Jun. 02, 2015 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020 | Dec. 14, 2020 | Sep. 12, 2019
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit agreement initiation date |  | Jun. 02, 2015 |  |  |  |  |
Senior unsecured revolving credit agreement |  | $ 225,000,000 |  |  |  |  |
Term loan under credit agreement |  | 50,000,000 |  |  |  |  |
Borrowings under credit agreement |  |  | $ 17,500,000 |  | $ 25,000,000 |  |
Repayment of borrowings under credit agreement, outstanding amount |  |  | $ 37,500,000 | $ 10,000,000 |  |  |
Series A Note [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Feb. 25, 2021 |  |  |  |
Fifth Amended and Restated Prudential Agreement [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note, issuance date |  |  | Dec. 04, 2020 |  |  |  |
Amount of rate increase in case of default |  |  | 2.00% |  |  |  |
Fifth Amended and Restated Prudential Agreement [Member] | Series A Note [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Feb. 25, 2021 |  |  |  |
Interest rate on agreement |  |  | 6.00% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 100,000,000 |  |  |  |
Loss on extinguishment of debt |  |  | $ 1,233,000 |  |  |  |
Fifth Amended and Restated Prudential Agreement [Member] | Series B Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Jun. 02, 2023 |  |  |  |
Interest rate on agreement |  |  | 5.35% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 75,000,000 |  |  |  |
Fifth Amended and Restated Prudential Agreement [Member] | Series C Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Feb. 25, 2025 |  |  |  |
Interest rate on agreement |  |  | 4.75% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 50,000,000 |  |  |  |
Fifth Amended and Restated Prudential Agreement [Member] | Series D Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Jun. 21, 2028 |  |  |  |
Interest rate on agreement |  |  | 5.47% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 50,000,000 |  |  |  |
Fifth Amended and Restated Prudential Agreement [Member] | Series F Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Sep. 12, 2029 |  |  |  |
Interest rate on agreement |  |  | 3.52% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 50,000,000 |  |  |  |
Fifth Amended and Restated Prudential Agreement [Member] | Series I Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Nov. 25, 2030 |  |  |  |
Interest rate on agreement |  |  | 3.43% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 100,000,000 |  |  |  |
Fourth Restated Prudential Note Purchase Agreement [Member] | Series E Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Jun. 21, 2018 |  |  |  |
Interest rate on agreement |  |  | 5.47% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 50,000,000 |  |  |  |
First Amended and Restated AIG Agreement [Member] | Series G Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Sep. 12, 2029 |  |  |  |
Interest rate on agreement |  |  | 3.52% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 50,000,000 |  |  |  |
First Amended and Restated AIG Agreement [Member] | Series J Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Nov. 25, 2030 |  |  |  |
Interest rate on agreement |  |  | 3.43% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 50,000,000 |  |  |  |
First Amended and Restated MassMutual Agreement [Member] | Series H Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Sep. 12, 2029 |  |  |  |
Interest rate on agreement |  |  | 3.52% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 25,000,000 |  |  |  |
First Amended and Restated MassMutual Agreement [Member] | Series K Notes [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Nov. 25, 2030 |  |  |  |
Interest rate on agreement |  |  | 3.43% |  |  |  |
Senior unsecured note, aggregate amount issued |  |  | $ 25,000,000 |  |  |  |
Revolving Facility [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Revolving facility under credit agreement | $ 175,000,000 | $ 175,000,000 |  |  |  |  | $ 250,000,000
Credit facility amount | $ 250,000,000 |  |  |  |  |  | 300,000,000
Credit agreement maturity date | Jun. 30, 2018 |  |  |  |  |  |
Credit agreement extended maturity date | Mar. 31, 2022 |  |  |  |  |  |
Credit facility agreement, optional extended maturity date |  |  | Mar. 31, 2023 |  |  |  |
Revolving facility optional extension period |  |  | 1 year |  |  |  |
Borrowings under credit agreement |  |  | $ 17,500,000 |  | $ 25,000,000 | $ 75,000,000 |
Senior unsecured note purchase agreement, maturity date |  |  | Mar. 31, 2022 |  | Mar. 31, 2022 |  |
Interest rate on agreement |  |  | 1.58% |  | 1.58% |  |
Repayment of borrowings under credit agreement, outstanding amount |  |  | $ 75,000,000 |  |  |  |
Revolving Facility [Member] | Maximum [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Option to increase credit facility |  |  | $ 300,000,000 |  |  |  |
Annual commitment fee on undrawn funds |  |  | 0.25% |  |  |  |
Revolving Facility [Member] | Maximum [Member] | Base Rate [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 1.30% |  |  |  |
Revolving Facility [Member] | Maximum [Member] | LIBOR [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 2.30% |  |  |  |
Revolving Facility [Member] | Minimum [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Annual commitment fee on undrawn funds |  |  | 0.15% |  |  |  |
Revolving Facility [Member] | Minimum [Member] | Base Rate [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 0.50% |  |  |  |
Revolving Facility [Member] | Minimum [Member] | LIBOR [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 1.50% |  |  |  |
Term Loan [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit facility amount |  |  | $ 600,000,000 |  |  |  | $ 0
Credit agreement maturity date | Jun. 30, 2020 |  |  |  |  |  |
Credit agreement extended maturity date | Mar. 31, 2023 |  |  |  |  |  |
Term Loan [Member] | Maximum [Member] | Base Rate [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 1.25% |  |  |  |
Term Loan [Member] | Maximum [Member] | LIBOR [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 2.25% |  |  |  |
Term Loan [Member] | Minimum [Member] | Base Rate [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 0.45% |  |  |  |
Term Loan [Member] | Minimum [Member] | LIBOR [Member] |  |  |  |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 1.45% |  |  |  |

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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the 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)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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