Leases (Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Leases.
Cash paid for amounts included in the measurement of operating lease liabilities, operating cash flows from operating leases	$ 82,607	$ 78,298
Right-of-use asset obtained in exchange for new operating lease liability	$ 71,131	$ 10,940