Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gross profit	$ 371,072	$ 397,701	$ 349,749
Research and development expense	25,800	26,900	29,800
Provision for credit losses from uncollected receivables and contract assets	1,628	309	579
Total equity	$ (819,865)	(702,689)	(608,280)	$ (573,015)
Receivable with imputed interest, effective yield (interest rate)	2.00%
Noncurrent receivables invoice terms (in years)	10 years
Assets for plan benefits, defined benefit plan	$ 31,100	21,300
Software | Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Useful life	5 years
Software | Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Useful life	8 years
Albany Safran Composites, LLC
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Noncontrolling interest, ownership percentage by parent	90.00%
Entity In Russia
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Noncontrolling interest, ownership percentage by parent	50.00%
Retained earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total equity	$ (770,746)	(698,496)	(589,645)	(534,082)
Share-based Payment Arrangement, Option
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Expiration period	20 years
Length of time options are valid after retirement, in years	10 years
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Provision for credit losses from uncollected receivables and contract assets		1,800
Total equity		1,443	(35)	5,395
Cumulative Effect, Period of Adoption, Adjustment | Retained earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total equity		1,443	(35)	$ 5,068
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings, Pre-Tax
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total equity		300	300
Long term contract
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gross profit	$ 9,900	10,800	$ (2,000)
Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Assets for plan benefits, defined benefit plan	$ 700	$ 800