Long-term Debt, Line of Credit and Derivatives - Financial covenants (Details)	3 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Aug. 05, 2015
Debt Instrument [Line Items]
Debt instrument, covenant, fixed charge coverage ratio, maximum					1.25
Debt instrument, covenant, leverage ratio, maximum			4.75	3.00
Scenario, Forecast
Debt Instrument [Line Items]
Debt instrument, covenant, leverage ratio, maximum	3.00	4.75