Leases (Schedule of Other Supplemental Information) (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 8,806	$ 17,981
Operating cash flows from finance leases	41	87
Financing cash flows from finance leases	218	435
Right-of-use assets obtained in exchange for new lease liabilities:
Right-of-use assets obtained in exchange for lease liabilities, operating leases	11,489	15,167
Right-of-use assets obtained in exchange for lease liabilities, financing leases	$ 226	$ 226
Weighted-average remaining lease term:
Weighted-average remaining lease term, operating leases	4 years 8 months 12 days	4 years 8 months 12 days
Weighted-average remaining lease term, finance leases	15 years 10 months 24 days	15 years 10 months 24 days
Weighted-average discount rate:
Weighted-average discount rate, operating leases	3.19%	3.19%
Weighted-average discount rate, finance leases	2.99%	2.99%