Fair Value Disclosure (Details) - Fair value measurements, recurring - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Assets:
Assets at fair value	$ 39	$ 0	$ 69
Liabilities:
Liabilities at fair value	1,338	390	408
Prepaid expenses and other current assets
Assets:
Interest rate swap agreements	0	0	69
Foreign currency exchange contracts	39	0	0
Other current liabilities
Liabilities:
Interest rate swap agreements	390	21	0
Foreign currency exchange contracts	0	308	357
Other long-term liabilities
Liabilities:
Interest rate swap agreements	$ 948	$ 61	$ 51