Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

Significant Accounting Policies [Abstract]

Detailed Information about Allowance for Doubtful Accounts

(Dollars in thousands)	2020		2019		2018
Allowance for doubtful accounts	$	2,502	$	1,756	$	1,343
Bad debt expense		255		455		843

Estimated Lives of Prperty, Plant and Equipment

Buildings	20 to 40 years
Machinery and equipment	5 to 15 years