Debt and Credit Agreements - Changes in the Balance of Deferred Debt Issuance Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Change In Debt Issuance Costs, Net [Roll Forward]
Balance	$ 4,583
Additions	2,321	$ 0	$ 2,106
Amortization	(2,204)	(2,292)	$ (1,590)
Balance	$ 4,700	$ 4,583