Recent Accounting Developments Recent Accounting Developments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Adjustments for New Accounting Pronouncements [Line Items]
Operating lease, right-of-use asset	$ 1,369,555			$ 0
Current maturities of operating leases	120,662			0
Operating leases, less current maturities	$ 1,218,014			$ 0
Accounting Standards Update 2016-02
Adjustments for New Accounting Pronouncements [Line Items]
Operating lease, right-of-use asset		$ 1,000,000
Current maturities of operating leases		128,100
Operating leases, less current maturities		$ 895,100
Restatement Adjustment | Accounting Standards Update 2016-02
Adjustments for New Accounting Pronouncements [Line Items]
Retained earnings impact of Topic 842 adoption			$ (5,500)