Summary of Significant Accounting Policies (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Foreign Currency Translation [Abstract]
Foreign currency transaction gains and (losses), net	$ (618)	$ 539	$ 431
Allowance for doubtful accounts [Roll Forward]
Allowance balance, beginning of year	1,184	1,716	1,511
Provision	1,249	223	482
Write offs	(1,016)	(696)	(308)
Other	(1)	(59)	31
Allowance balance, end of year	1,416	1,184	1,716
Revenue Recognition [Abstract]
Net sales	1,169,613	1,171,599	1,184,739
Contract assets	4,660
Contract liabilities	6,511
Advertising Expense [Abstract]
Advertising costs	$ 3,668	$ 4,136	$ 3,793
Denominator [Abstract]
Denominator for basic earnings (loss) per share (in shares)	22,515	22,902	23,025
Effect of dilutive securities [Abstract]
Restricted stock units (in shares)	111	0	96
Supplemental executive retirement plan (in shares)	48	0	63
Denominator for diluted earnings (loss) per share (in shares)	22,674	22,902	23,184
Minimum [Member]
Product Warranty Reserve [Abstract]
Product warranty reserve term	three months
Maximum [Member]
Product Warranty Reserve [Abstract]
Product warranty reserve term	two years
Extended Warranty Revenue [Member]
Revenue Recognition [Abstract]
Net sales	$ 1,895
Deferred revenue	3,536
Energy Group [Member]
Revenue Recognition [Abstract]
Net sales	272,122	$ 276,146
Energy Group [Member] | One Large Order [Member]
Revenue Recognition [Abstract]
Net sales	$ 7,249
Airplanes [Member]
Useful Lives [Abstract]
Estimated useful lives of assets	20 years
Buildings [Member]
Useful Lives [Abstract]
Estimated useful lives of assets	40 years
Equipment [Member] | Minimum [Member]
Useful Lives [Abstract]
Estimated useful lives of assets	3 years
Equipment [Member] | Maximum [Member]
Useful Lives [Abstract]
Estimated useful lives of assets	10 years
Astec do Brasil Fabricacao de Equipamentos LTDA [Member]
Basis of Presentation [Abstract]
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Percentage	93.00%
General Liability Insurance [Member]
Self-Insurance Reserves [Abstract]
Amount captive is liable per occurrence of claims	$ 1,000
Workers' Compensation Insurance [Member]
Self-Insurance Reserves [Abstract]
Amount captive is liable per occurrence of claims	$ 350
Dealer Network and Customer Relationships [Member] | Minimum [Member]
Estimated useful lives of definite lived intangible assets [Abstract]
Estimated useful lives of intangible assets	8 years
Dealer Network and Customer Relationships [Member] | Maximum [Member]
Estimated useful lives of definite lived intangible assets [Abstract]
Estimated useful lives of intangible assets	19 years
Trade Names [Member] | Minimum [Member]
Estimated useful lives of definite lived intangible assets [Abstract]
Estimated useful lives of intangible assets	14 years
Trade Names [Member] | Maximum [Member]
Estimated useful lives of definite lived intangible assets [Abstract]
Estimated useful lives of intangible assets	15 years
Other [Member] | Minimum [Member]
Estimated useful lives of definite lived intangible assets [Abstract]
Estimated useful lives of intangible assets	3 years
Other [Member] | Maximum [Member]
Estimated useful lives of definite lived intangible assets [Abstract]
Estimated useful lives of intangible assets	19 years
ASU 2018-02 [Member] | Accumulated Other Comprehensive Loss [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification of stranded tax effects related to TCJA	$ (721)
ASU 2018-02 [Member] | Retained Earnings [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification of stranded tax effects related to TCJA	$ 721