Leases (Summary of Maturity of Lease Liabilities) (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Operating Leases
2019	$ 27,419
2020	35,909
2021	31,248
2022	33,309
2023	33,766
Thereafter	118,885
Total lease payments	280,536
Less: Interest	49,568
Present value of lease liabilities	230,968
Finance Leases
2019	5,627
2020	5,862
2021	4,388
2022	4,414
2023	4,441
Thereafter	9,673
Total lease payments	34,405
Less: Interest	9,348
Present value of lease liabilities	25,057
Total
2019	33,046
2020	41,771
2021	35,636
2022	37,723
2023	38,207
Thereafter	128,558
Total lease payments	314,941
Less: Interest	58,916
Total lease liabilities	$ 256,025