Borrowings - 2022 Notes (Details) - 2022 Notes - Senior Notes - USD ($)	Dec. 14, 2017	Jun. 30, 2022
Debt Instrument [Line Items]
Aggregate principal amount	$ 150,000,000
Interest Rate	4.75%	4.75%
Proceeds from sale	$ 147,000,000
Discount price	800,000
Discounts and commissions	1,700,000
Estimated offering expenses	$ 600,000

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.

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