Related Party Transactions and Arrangements - Schedule Of Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment (Detail) - USD ($)												3 Months Ended
	Dec. 31, 2025	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2026	Mar. 31, 2023
March 31, 2029 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense												$ 219,785
Yearly expense limitation												89,086
Yearly cumulative expense reimbursement												130,699
Quarterly recoupable/ (recouped) amount												$ 130,699
Recoupment eligibility expiration												Mar. 31, 2029
December 31, 2028 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense	$ 915,414
Yearly expense limitation	385,405
Yearly cumulative expense reimbursement	530,009
Quarterly recoupable/ (recouped) amount	$ 127,754
Recoupment eligibility expiration	Dec. 31, 2028
September 30, 2028 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense		$ 687,933
Yearly expense limitation		285,678
Yearly cumulative expense reimbursement		402,255
Quarterly recoupable/ (recouped) amount		$ 136,100
Recoupment eligibility expiration		Sep. 30, 2028
June 30, 2028 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense			$ 467,440
Yearly expense limitation			201,285
Yearly cumulative expense reimbursement			266,155
Quarterly recoupable/ (recouped) amount			$ 145,163
Recoupment eligibility expiration			Jun. 30, 2028
March 31, 2028 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense				$ 225,789
Yearly expense limitation				104,797
Yearly cumulative expense reimbursement				120,992
Quarterly recoupable/ (recouped) amount				$ 120,992
Recoupment eligibility expiration				Mar. 31, 2028
December 31, 2027 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense					$ 913,667
Yearly expense limitation					437,693
Yearly cumulative expense reimbursement					475,974
Quarterly recoupable/ (recouped) amount					$ 148,020
Recoupment eligibility expiration					Dec. 31, 2027
September 30, 2027 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense						$ 700,195
Yearly expense limitation						372,241
Yearly cumulative expense reimbursement						327,954
Quarterly recoupable/ (recouped) amount						$ 79,981
Recoupment eligibility expiration						Sep. 30, 2027
June 30, 2027 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense							$ 468,715
Yearly expense limitation							220,742
Yearly cumulative expense reimbursement							247,973
Quarterly recoupable/ (recouped) amount							$ 128,092
Recoupment eligibility expiration							Jun. 30, 2027
March 31, 2027 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense								$ 232,187
Yearly expense limitation								112,306
Yearly cumulative expense reimbursement								119,881
Quarterly recoupable/ (recouped) amount								$ 119,881
Recoupment eligibility expiration								Mar. 31, 2027
December 31, 2026 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense									$ 902,219
Yearly expense limitation									481,443
Yearly cumulative expense reimbursement									420,776
Quarterly recoupable/ (recouped) amount									$ 140,233
Recoupment eligibility expiration									Dec. 31, 2026
September 30, 2026 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense										$ 630,925
Yearly expense limitation										350,382
Yearly cumulative expense reimbursement										280,543
Quarterly recoupable/ (recouped) amount										$ 96,669
Recoupment eligibility expiration										Sep. 30, 2026
June 30, 2026 [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense											$ 420,066
Yearly expense limitation											236,192
Yearly cumulative expense reimbursement											183,874
Quarterly recoupable/ (recouped) amount											$ 102,016
Recoupment eligibility expiration											Jun. 30, 2026
Expired [Member]
Fee Waivers And Expense Reimbursements Due From The Adviser Which May Become Subject To Recoupment [Line Items]
Yearly cumulative other expense													$ 208,486
Yearly expense limitation													126,628
Yearly cumulative expense reimbursement													81,858
Quarterly recoupable/ (recouped) amount													$ 81,858

NexPoint Capital, Inc. 10-Q