Consolidated Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2022		Dec. 31, 2021		Dec. 31, 2020
Cash flows from operating activities:
Net increase (decrease) in net assets resulting from operations		$ 15,544		$ 83,633		$ 54,672
Adjustments to reconcile net increase (decrease) in net assets resulting from operations to net cash provided by (used for) operating activities:
Purchases of investments		(307,998)		(647,376)		(352,392)
Paid-in-kind interest income		(4,455)		(3,148)		(3,625)
Proceeds from sales of investments and principal repayments		277,566		461,268		258,979
Net realized (gain) loss on investments, foreign currency transactions and foreign currency forward contracts		(4,886)		(33,162)		15,786
Realized loss on asset acquisition	[1]					3,825
Acquisition of Alcentra Capital Corporation, net of cash acquired	[1]					(12,884)
Net change in unrealized (appreciation) depreciation on investments and foreign currency translation		54,837		(2,673)		(25,416)
Net change in unrealized (appreciation) depreciation on foreign currency forward contracts		(6,513)		(2,116)		1,324
Amortization of premium and accretion of discount, net		(6,854)		(11,284)		(5,109)
Amortization of deferred financing costs		1,738		2,554		1,329
Change in operating assets and liabilities:
(Increase) decrease in receivable for investments sold		14,866		(14,865)		549
(Increase) decrease in interest receivable		(3,182)		(2,904)		(25)
(Increase) decrease in deferred tax asset		(49)		588		(209)
(Increase) decrease in other assets		(4,534)		417		2,480
Increase (decrease) in management fees payable		226		1,963		524
Increase (decrease) in incentive fees payable		(3,812)		6,924
Increase (decrease) in directors’ fees payable		37		16		24
Increase (decrease) in interest and other debt financing costs payable		2,958		1,590		(456)
Increase (decrease) in deferred tax liability		(57)		(368)		445
Increase (decrease) in payable for investment sold		514
Increase (decrease) in accrued expenses and other liabilities		2,005		1,289		(1,620)
Net cash provided by (used for) operating activities		27,951		(157,654)		(61,799)
Cash flows from financing activities:
Issuance of common stock				52,632		44,297
Deemed contribution from the Advisor (Note 3)				5,386
Repurchase of common stock						(2,208)
Deferred financing and debt issuance costs paid		(221)		(4,851)		(2,498)
Distributions paid		(55,288)		(47,728)		(42,632)
Equity offering cost				(523)
Borrowings on credit facilities		339,215		654,974		352,342
Repayments on credit facilities		(318,111)		(612,151)		(302,227)
Issuance of unsecured debt				135,000		50,000
Repayments on InterNotes				(16,418)		(33,853)
Net cash provided by (used for) financing activities		(34,405)		166,321		63,221
Effect of exchange rate changes on cash denominated in foreign currency		(5)		10
Net increase (decrease) in cash, cash equivalents, restricted cash and foreign currency		(6,459)		8,677		1,422
Cash, cash equivalents, restricted cash and foreign currency, beginning of period		23,526	[2]	14,849	[2]	13,427
Cash, cash equivalents, restricted cash and foreign currency, end of period	[2]	17,067		23,526		14,849
Supplemental and non-cash financing activities:
Cash paid during the period for interest		26,903		15,474		14,489
Cash paid during the period for taxes		1,974		2,176		692
Issuance of common stock pursuant to dividend reinvestment plan						589
Accrued but unpaid distributions		$ 12,664		$ 12,664		11,549
Issuance of shares in connection with asset acquisition (Note 14)						$ 101,949

[1] After the close of business on January 31, 2020, in connection with the Alcentra Acquisition (as defined in Note 1 and further discussed in Note 14), the Company acquired net assets of $114,431 which included $195,682 of investments, $3,409 cash and cash equivalents and $1,398 of other assets, net of $86,058 of assumed liabilities, for the total cash and stock consideration of $118,256, inclusive of $7,250 of asset acquisition costs.

[2] As of December 31, 2022, the balance included cash and cash equivalents of $6,397 (including cash denominated in foreign currency of $125) and restricted cash and cash equivalents of $10,670. As of December 31, 2021, the balance included cash and cash equivalents of $10,069 (including cash denominated in foreign currency of $1,064) and restricted cash and cash equivalents of $13,457 (including cash denominated in foreign currency of $743). As of December 31, 2020, the balance included cash and cash equivalents of $1,746 (including cash denominated in foreign currency of $132) and restricted cash and cash equivalents of $12,953.