CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 70,062	$ 41,250
Restricted cash	4,461	3,698
Accounts receivable, net of allowances of $1,734 and $967 as of June 30, 2026 and December 31, 2025, respectively; (from related parties $200 and $415 as of June 30, 2026 and December 31, 2025, respectively)	80,180	90,446
Income tax receivable	2,879	6,442
Inventories, net	127,582	127,363
Prepaid expenses	3,859	4,500
Contract assets	12,507	15,965
Other current assets	1,004	1,256
Total current assets	302,534	290,920
Property, plant and equipment, net	31,908	23,014
Operating lease right-of-use assets, net	59,267	52,911
Intangible assets, net	1,327	1,236
Goodwill	34,921	29,835
Deferred tax assets	9,517	13,322
Customs-related deposits	13,424	12,893
Other noncurrent assets	419	614
TOTAL ASSETS	453,317	424,745
Current liabilities:
Accounts payable (to related parties $8,700 and $4,126 as of June 30, 2026 and December 31, 2025, respectively)	49,508	48,196
Tariff refund liability	22,687	0
Current maturities of long-term debt	935	28
Finance lease liability, current	397	355
Operating lease liability, current	7,561	6,346
Other short-term financing	250	0
Other accrued liabilities (to related parties $53 and $60 as of June 30, 2026 and December 31, 2025, respectively)	36,247	37,353
Total current liabilities	117,585	92,278
Long-term debt, net of current maturities	4,848	10
Revolving line of credit, long-term	65,000	95,000
Finance lease liability, long-term	1,219	1,224
Operating lease liability, long-term	53,676	49,397
Noncurrent contract liabilities	1,649	1,699
Other noncurrent liabilities	6,272	6,528
TOTAL LIABILITIES	250,249	246,136
Commitments and Contingencies (Note 11)
STOCKHOLDERS’ EQUITY
Common stock – $0.001 par value; 50,000 shares authorized; 23,117 shares issued; 23,050 and 23,041 shares outstanding at June 30, 2026 and December 31, 2025, respectively	23	23
Additional paid-in capital	158,308	157,602
Retained earnings	46,637	22,476
Treasury stock, at cost, 67 and 76 shares at June 30, 2026 and December 31, 2025, respectively	(1,900)	(1,492)
TOTAL STOCKHOLDERS’ EQUITY	203,068	178,609
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 453,317	$ 424,745

IEEPA Tariff Refund Liability, Current

No definition available.

Name:	psix_IEEPATariffRefundLiabilityCurrent
Namespace Prefix:	psix_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).