BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Segment Disclosures (Details) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2025 USD ($)	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2025 USD ($) segment	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES
Number of reportable segments \| segment							1
CONSOLIDATED STATEMENT OF INCOME
NET SALES	$ 178,670			$ 314,271			$ 618,353	$ 1,035,593
Cost of operations	153,338			272,245			524,491	898,246
Selling, general and administrative expenses	21,247			22,326			67,912	66,642
Interest expense, net	93			251			482	3,544
Other (income) expense, net	312			321			994	341
Income before taxes	4,304			19,770			26,462	67,502
Tax expense	1,222			4,345			6,857	14,540
NET INCOME	3,082	$ 8,458	$ 8,065	15,425	$ 20,514	$ 17,023	19,605	52,962
TOTAL ASSETS
Cash and temporary investments	38,401			40,600			38,401	40,600	$ 24,337	$ 29,909
Accounts receivable, net of allowance for credit losses	232,617						232,617		313,413
Inventories, net	180,715						180,715		186,169
Prepaid expenses	17,733						17,733		5,847
Long-lived assets:
Net long-lived assets	133,877						133,877		136,522
Other assets	1,000						1,000		727
TOTAL ASSETS	604,343						604,343		667,015
North America
CONSOLIDATED STATEMENT OF INCOME
NET SALES	148,030			286,558			510,310	945,794
Long-lived assets:
Net long-lived assets	125,314						125,314		129,181
Foreign
CONSOLIDATED STATEMENT OF INCOME
NET SALES	30,640
Long-lived assets:
Net long-lived assets	$ 8,564						8,564		$ 7,341
Single reporting segment
CONSOLIDATED STATEMENT OF INCOME
NET SALES				314,271			618,353	1,035,593
Cost of operations				272,245			524,491	898,246
Selling, general and administrative expenses				22,326			67,912	66,642
Interest expense, net				251			482	3,544
Other (income) expense, net				321			994	341
Income before taxes				19,770			26,462	67,502
Tax expense				4,345			6,857	14,540
NET INCOME				15,425			19,605	52,962
Single reporting segment \| North America
CONSOLIDATED STATEMENT OF INCOME
NET SALES				286,558			510,310	945,794
Single reporting segment \| Foreign
CONSOLIDATED STATEMENT OF INCOME
NET SALES				$ 27,713			$ 108,043	$ 89,799

MILLER INDUSTRIES INC /TN/ 10-Q