Revenue Recognition (Tables)

12 Months Ended

Dec. 31, 2018

Revenue from Contract with Customer [Abstract]

Contract with Customer, Asset and Liability

The timing of revenue recognition, billings and cash collections resulted in the following contract assets and contract liabilities:

(Thousands)	December 31, 2018		January 1, 2018		$ change		% change
Accounts receivable, trade	$	124,498	$	122,393	$	2,105	2	%
Unbilled receivables	4,619		2,658		1,961		74	%
Unearned revenue	5,918		5,451		467		9	%