Leases (Supplemental Cash Flows Information) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 16,736
Financing cash flows from finance leases	1,124
ROU assets obtained in exchange for lease obligations:
Operating leases	2,922
Finance leases	$ 3,580
Weighted average remaining lease term (in years)
Operating leases	9 years
Finance leases	3 years
Weighted average discount rate (percent)
Operating leases	4.50%
Finance leases	3.60%