Leases (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operarting lease expense	$ 10,105,000	$ 13,500,000	$ 29,433,000	$ 40,400,000
2019					$ 30,800,000
2020					24,300,000
2021					16,600,000
2022					9,800,000
2023					6,900,000
Thereafter					37,800,000
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect of change in accounting principle					100,000,000.0
Equity impact of adoption					$ 0