CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
CURRENT ASSETS:
Cash	$ 105,037	$ 72,031
Accounts receivable, less allowances for discounts and expected credit losses of $10,395 and $10,043 for 2026 and 2025, respectively	307,149	232,020
Inventories	646,139	727,922
Prepaid expenses and other current assets	23,924	18,477
Total current assets	1,082,249	1,050,450
Property, plant and equipment, net of accumulated depreciation of $309,409 and $300,283 for 2026 and 2025, respectively	187,836	188,562
Operating lease right-of-use assets	98,254	105,178
Goodwill	251,877	256,159
Customer relationships intangibles, net	193,720	212,056
Other intangibles, net	95,228	99,102
Deferred income taxes	24,732	25,384
Investments in unconsolidated affiliates	27,583	26,310
Other assets	37,034	32,040
Total assets	1,998,513	1,995,241
CURRENT LIABILITIES:
Current portion of revolving credit facility	50,000	30,000
Current portion of term loan and other debt	21,130	21,988
Accounts payable	166,608	169,089
Sundry payables and accrued expenses	115,232	92,054
Accrued customer returns	76,953	49,554
Accrued rebates	124,679	84,494
Payroll and commissions	44,638	46,135
Total current liabilities	599,240	493,314
Long-term debt	415,830	566,727
Noncurrent operating lease liabilities	87,220	93,381
Accrued asbestos liabilities	123,345	112,625
Other accrued liabilities	31,879	30,932
Total liabilities	1,257,514	1,296,979
Commitments and contingencies
Stockholders’ equity:
Common stock – par value $2.00 per share (Authorized – 30,000,000 shares; issued 23,936,036 shares)	47,872	47,872
Capital in excess of par value	103,177	99,005
Retained earnings	629,060	589,448
Accumulated other comprehensive income	8,796	17,857
Treasury stock – at cost (1,594,225 shares and 1,790,097 shares in 2026 and 2025, respectively)	(62,794)	(70,483)
Total SMP stockholders’ equity	726,111	683,699
Noncontrolling interest	14,888	14,563
Total stockholders’ equity	740,999	698,262
Total liabilities and stockholders’ equity	$ 1,998,513	$ 1,995,241

Accrued Customer Returns

No definition available.

Name:	smp_AccruedCustomerReturns
Namespace Prefix:	smp_
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).