Leases (Lease Cost) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Leases [Abstract]
Lease cost	$ 10,680	$ 22,235
Cash paid for amounts included in the measurement of lease liabilities reported in operating cash flows	11,132	22,789
Right-of-use assets obtained in exchange for new lease liabilities	$ 2,918	$ 7,884