Financial Highlights - Schedule of Financial Highlights (Detail) - USD ($)	3 Months Ended								11 Months Ended	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Feb. 07, 2018
OPERATING PERFORMANCE PER SHARE
Net investment income (usd per share)	$ 0.24	$ 0.26	$ 0.27	$ 0.28	$ 0.29	$ 0.30	$ 0.31	$ 0.09	$ 1.00	$ 1.05	$ 1.00
Net assets at end of period	$ 174,282,891				$ 102,829,810				$ 102,829,810	$ 174,282,891	$ 102,829,810	$ 200,000
Investment Company, Dividend Distribution									$ 3,518,302	$ 5,845,584
Class FA
Investment Company, Financial Highlights [Line Items]
Investment Company, Total Return Incentive Fees Covered By Expense Support									30.00%	100.00%
OPERATING PERFORMANCE PER SHARE
Net Asset Value, Beginning of Period (usd per shares)	$ 27.34	27.19	26.72	26.65	$ 26.41	25.43	25.16		$ 25.00	$ 26.65
Net investment income, before expense support (usd per shares)									0.93	0.90
Expense support (usd per shares)									0.08	0.31
Net investment income (usd per share)									1.01	1.21
Net realized and unrealized gains (usd per shares)									1.67	1.03
Net increase resulting from investment operations (usd per shares)	0.61	0.46	0.79	0.38	0.55	1.30	0.58	0.25	2.68	2.24	$ 2.68
Distributions from net investment income (usd per share)									(1.03)	(1.25)
Net Decrease Resulting From Distributions to Shareholders, Per Share (usd per shares)									(1.03)	(1.25)
Net Asset Value, End of Period (usd per shares)	$ 27.64	27.34	27.19	26.72	$ 26.65	26.41	25.43	$ 25.16	$ 26.65	$ 27.64	$ 26.65
Net assets at end of period	$ 117,637,467				$ 87,061,758				$ 87,061,758	$ 117,637,467	$ 87,061,758
Average net assets	$ 92,567,951				$ 83,797,239				$ 83,797,239	$ 92,567,951	$ 83,797,239
Shares outstanding end of period (in shares)	4,255,547.77				3,266,260				3,266,260	4,255,547.77	3,266,260
Investment Company, Dividend Distribution									$ 3,364,900	$ 4,268,395
Total investment return based on net asset value before total return incentive fee									11.72%	8.46%
Investment Company, Total Return after Incentive Fees									10.88%	8.46%
Investment Company Operating Expenses Before Total Return Incentive Fee and Expense Support									2.87%	2.08%
Ratios to average net assets:
Total operating expenses before expense support									4.00%	2.92%
Net investment income before total return incentive fee(9)									3.66%	1.77%
Investment Company, Net Investment Income Before Incentive Fees									4.73%	4.47%
Net investment income after total return incentive fee									3.94%	4.47%
Class A
Investment Company, Financial Highlights [Line Items]
Investment Company, Total Return Incentive Fees Covered By Expense Support									100.00%	0.00%
OPERATING PERFORMANCE PER SHARE
Net Asset Value, Beginning of Period (usd per shares)	$ 26.74	26.74	26.39	26.44	$ 26.28	25.37			$ 25.00	$ 26.44
Net investment income, before expense support (usd per shares)									(1.26)	0.50
Expense support (usd per shares)									1.74	0.13
Net investment income (usd per share)									0.48	0.63
Net realized and unrealized gains (usd per shares)									1.87	1.09
Net increase resulting from investment operations (usd per shares)	0.48	0.31	0.67	0.26	0.47	1.22	0.66		2.35	1.72	$ 2.35
Distributions from net investment income (usd per share)									(0.91)	(1.25)
Net Decrease Resulting From Distributions to Shareholders, Per Share (usd per shares)									(0.91)	(1.25)
Net Asset Value, End of Period (usd per shares)	$ 26.91	26.74	26.74	26.39	$ 26.44	26.28	25.37		$ 26.44	$ 26.91	$ 26.44
Net assets at end of period	$ 18,008,048				$ 5,086,607				$ 5,086,607	$ 18,008,048	$ 5,086,607
Average net assets	$ 11,801,755				$ 562,185				$ 562,185	$ 11,801,755	$ 562,185
Shares outstanding end of period (in shares)	669,140.56				192,388				192,388	669,140.56	192,388
Investment Company, Dividend Distribution									$ 21,184	$ 549,420
Total investment return based on net asset value before total return incentive fee									9.56%	6.66%
Investment Company, Total Return after Incentive Fees									9.56%	6.66%
Investment Company Operating Expenses Before Total Return Incentive Fee and Expense Support									18.09%	4.89%
Ratios to average net assets:
Total operating expenses before expense support									19.62%	4.89%
Net investment income before total return incentive fee(9)									13.02%	4.38%
Investment Company, Net Investment Income Before Incentive Fees									1.81%	2.36%
Net investment income after total return incentive fee									1.81%	2.36%
Class T
Investment Company, Financial Highlights [Line Items]
Investment Company, Total Return Incentive Fees Covered By Expense Support									100.00%	0.00%
OPERATING PERFORMANCE PER SHARE
Net Asset Value, Beginning of Period (usd per shares)	$ 26.84	26.84	26.50	26.54	$ 26.36	25.42			$ 25.16	$ 26.54
Net investment income, before expense support (usd per shares)									(0.11)	(0.10)
Expense support (usd per shares)									0.52	0.42
Net investment income (usd per share)									0.41	0.32
Net realized and unrealized gains (usd per shares)									1.57	1.15
Net increase resulting from investment operations (usd per shares)	0.42	0.25	0.59	0.21	0.43	1.19	0.36		1.98	1.47	$ 1.98
Distributions from net investment income (usd per share)									(0.60)	(1.00)
Net Decrease Resulting From Distributions to Shareholders, Per Share (usd per shares)									(0.60)	(1.00)
Net Asset Value, End of Period (usd per shares)	$ 27.01	26.84	26.84	26.50	$ 26.54	26.36	25.42		$ 26.54	$ 27.01	$ 26.54
Net assets at end of period	$ 5,366,259				$ 834,576				$ 834,576	$ 5,366,259	$ 834,576
Average net assets	$ 2,079,541				$ 385,874				$ 385,874	$ 2,079,541	$ 385,874
Shares outstanding end of period (in shares)	198,662.05				31,452				31,452	198,662.05	31,452
Investment Company, Dividend Distribution									$ 9,032	$ 76,739
Total investment return based on net asset value before total return incentive fee									7.94%	5.65%
Investment Company, Total Return after Incentive Fees									7.94%	5.65%
Investment Company Operating Expenses Before Total Return Incentive Fee and Expense Support									6.15%	7.71%
Ratios to average net assets:
Total operating expenses before expense support									7.34%	7.71%
Net investment income before total return incentive fee(9)									5.37%	6.14%
Investment Company, Net Investment Income Before Incentive Fees									1.55%	1.20%
Net investment income after total return incentive fee									1.55%	1.20%
Class D
Investment Company, Financial Highlights [Line Items]
Investment Company, Total Return Incentive Fees Covered By Expense Support									0.00%	0.00%
OPERATING PERFORMANCE PER SHARE
Net Asset Value, Beginning of Period (usd per shares)	$ 26.43	26.46	26.17	26.23	$ 26.20	25.41			$ 25.26	$ 26.23
Net investment income, before expense support (usd per shares)									0.02	0.46
Expense support (usd per shares)									0.00	0.00
Net investment income (usd per share)									0.02	0.46
Net realized and unrealized gains (usd per shares)									1.53	1.04
Net increase resulting from investment operations (usd per shares)	0.46	0.25	0.57	0.22	0.31	1.07	0.17		1.55	1.50	$ 1.55
Distributions from net investment income (usd per share)									(0.58)	(1.12)
Net Decrease Resulting From Distributions to Shareholders, Per Share (usd per shares)									(0.58)	(1.12)
Net Asset Value, End of Period (usd per shares)	$ 26.61	26.43	26.46	26.17	$ 26.23	26.20	25.41		$ 26.23	$ 26.61	$ 26.23
Net assets at end of period	$ 8,053,103				$ 3,222,865				$ 3,222,865	$ 8,053,103	$ 3,222,865
Average net assets	$ 5,248,921				$ 1,732,979				$ 1,732,979	$ 5,248,921	$ 1,732,979
Shares outstanding end of period (in shares)	302,632.17				122,889				122,889	302,632.17	122,889
Investment Company, Dividend Distribution									$ 39,313	$ 222,967
Total investment return based on net asset value before total return incentive fee									6.80%	5.87%
Investment Company, Total Return after Incentive Fees									6.19%	5.87%
Investment Company Operating Expenses Before Total Return Incentive Fee and Expense Support									4.86%	4.97%
Ratios to average net assets:
Total operating expenses before expense support									5.92%	4.97%
Net investment income before total return incentive fee(9)									5.92%	4.97%
Investment Company, Net Investment Income Before Incentive Fees									1.15%	1.74%
Net investment income after total return incentive fee									0.09%	1.74%
Class I
Investment Company, Financial Highlights [Line Items]
Investment Company, Total Return Incentive Fees Covered By Expense Support									100.00%	100.00%
OPERATING PERFORMANCE PER SHARE
Net Asset Value, Beginning of Period (usd per shares)	$ 26.95	26.91	26.54	26.55	$ 26.34	25.40			$ 25.00	$ 26.55
Net investment income, before expense support (usd per shares)									0.06	0.40
Expense support (usd per shares)									0.69	0.36
Net investment income (usd per share)									0.75	0.76
Net realized and unrealized gains (usd per shares)									1.69	1.09
Net increase resulting from investment operations (usd per shares)	0.51	0.35	0.69	0.30	0.52	1.25	0.67		2.44	1.85	$ 2.44
Distributions from net investment income (usd per share)									(0.89)	(1.25)
Net Decrease Resulting From Distributions to Shareholders, Per Share (usd per shares)									(0.89)	(1.25)
Net Asset Value, End of Period (usd per shares)	$ 27.15	$ 26.95	$ 26.91	$ 26.54	$ 26.55	$ 26.34	$ 25.40		$ 26.55	$ 27.15	$ 26.55
Net assets at end of period	$ 25,218,014				$ 6,624,004				$ 6,624,004	$ 25,218,014	$ 6,624,004
Average net assets	$ 15,749,822				$ 2,381,673				$ 2,381,673	$ 15,749,822	$ 2,381,673
Shares outstanding end of period (in shares)	928,848.4				249,526				249,526	928,848.4	249,526
Investment Company, Dividend Distribution									$ 83,873	$ 728,063
Total investment return based on net asset value before total return incentive fee									9.90%	7.14%
Investment Company, Total Return after Incentive Fees									9.90%	7.14%
Investment Company Operating Expenses Before Total Return Incentive Fee and Expense Support									6.68%	4.81%
Ratios to average net assets:
Total operating expenses before expense support									8.40%	5.26%
Net investment income before total return incentive fee(9)									5.75%	3.89%
Investment Company, Net Investment Income Before Incentive Fees									2.87%	2.84%
Net investment income after total return incentive fee									2.87%	2.84%