Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Retirement Benefits [Abstract]
Defined benefit plan, expected future employer contributions, remainder of fiscal year	$ 1.0
Defined benefit plan, employer contributions		$ 1.0
Defined contribution plan, compensation expense	$ 1.0	$ 0.9