Business Segment and Geographical Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 28, 2013		Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 29, 2012		Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 28, 2013 Segment		Dec. 29, 2012		Dec. 31, 2011
Business Segment and Geographical Information [Abstract]
Number of reportable segments											2
Segment Reporting Information [Line Items]
Restructuring and other expense (income), net (Note 8)											$ 103		$ 307		$ (1,874)
Revenues by Product line [Abstract]
Revenues	94,815		91,315	82,165	76,204	78,055		86,601	82,982	84,113	344,499		331,751		335,460
Income from Continuing Operations Before Provision for Income Taxes [Abstract]
Total operating income											33,303		36,444		38,710
Interest expense, net											(277)		(514)		(567)
Income from Continuing Operations Before Provision for Income Taxes											33,026		35,930		38,143
Total Assets [Abstract]
Total Assets from Continuing Operations	442,024					358,435					442,024		358,435		356,723
Total Assets from Discontinued Operations	144					513					144		513		1,675
Total Assets	442,168					358,948					442,168		358,948		358,398
Depreciation and Amortization [Abstract]
Depreciation and amortization											9,775		8,384		7,936
Capital Expenditures [Abstract]
Capital expenditures											6,261		4,250		8,030
Revenues and Long-Lived Assets by Geographic Area [Line Items]
Revenue from external customers by geographic area											344,499	[1]	331,751	[1]	335,460	[1]
Long-lived assets	44,885	[2]				39,168	[2]				44,885	[2]	39,168	[2]	40,095	[2]
Export Revenues Included in United States Revenues Above											9,685	[3]	20,871	[3]	16,512	[3]
United States [Member]
Revenues and Long-Lived Assets by Geographic Area [Line Items]
Revenue from external customers by geographic area											129,131	[1]	128,663	[1]	123,614	[1]
Long-lived assets	14,118	[2]				13,702	[2]				14,118	[2]	13,702	[2]	14,578	[2]
China [Member]
Revenues and Long-Lived Assets by Geographic Area [Line Items]
Revenue from external customers by geographic area											50,678	[1]	53,242	[1]	62,615	[1]
Long-lived assets	14,603	[2]				15,136	[2]				14,603	[2]	15,136	[2]	15,789	[2]
Other [Member]
Revenues and Long-Lived Assets by Geographic Area [Line Items]
Revenue from external customers by geographic area											164,690	[1]	149,846	[1]	149,231	[1]
Long-lived assets	16,164	[2]				10,330	[2]				16,164	[2]	10,330	[2]	9,728	[2]
Papermaking Systems [Member]
Segment Reporting Information [Line Items]
Restructuring and other expense (income), net (Note 8)											103		307		(1,874)
Revenues by Product line [Abstract]
Revenues											328,708		321,026		324,865
Income from Continuing Operations Before Provision for Income Taxes [Abstract]
Income from Continuing Operations Before Provision for Income Taxes											47,144	[4]	48,618	[4]	50,869	[4]
Total Assets [Abstract]
Total Assets from Continuing Operations	364,102					347,540					364,102		347,540		340,227
Depreciation and Amortization [Abstract]
Depreciation and amortization											8,434		7,903		7,455
Capital Expenditures [Abstract]
Capital expenditures											5,843		3,982		7,751
Papermaking Systems [Member] | Stock-preparation [Member]
Revenues by Product line [Abstract]
Revenues											122,704		123,952		131,914
Papermaking Systems [Member] | Doctoring, Cleaning and Filtration [Member]
Revenues by Product line [Abstract]
Revenues											112,600		104,493		92,333
Papermaking Systems [Member] | Fluid-handling [Member]
Revenues by Product line [Abstract]
Revenues											93,404		92,581		100,618
Fiber based Products [Member]
Revenues by Product line [Abstract]
Revenues											11,218		10,725		10,595
Corporate and Fiber-based Products [Member]
Income from Continuing Operations Before Provision for Income Taxes [Abstract]
Income from Continuing Operations Before Provision for Income Taxes											(13,459)		(12,174)		(12,159)
Total Assets [Abstract]
Total Assets from Continuing Operations	14,429	[5]				10,895	[5]				14,429	[5]	10,895	[5]	16,496	[5]
Depreciation and Amortization [Abstract]
Depreciation and amortization											1,341		481		481
Capital Expenditures [Abstract]
Capital expenditures											418		268		279
Wood Processing Systems Segment [Member]
Revenues by Product line [Abstract]
Revenues											4,573		0		0
Income from Continuing Operations Before Provision for Income Taxes [Abstract]
Income from Continuing Operations Before Provision for Income Taxes											(382)		0		0
Total Assets [Abstract]
Total Assets from Continuing Operations	$ 63,493					$ 0					$ 63,493		$ 0		$ 0

[1] Revenues are attributed to countries based on customer location.

[2] Represents property, plant, and equipment, net.

[3] In general, export revenues are denominated in U.S. dollars.

[4] Includes restructuring costs and other expense (income) net, including costs of $0.1 million and $0.3 million in 2013 and 2012, respectively, and income of $1.9 million in 2011.

[5] Primarily includes cash and cash equivalents and property, plant, and equipment.