Significant Accounting Policies - New Accounting Pronouncements (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets, net	$ 768,747	$ 861,878
Cumulative effect on retained earnings, net of tax			$ 28,944
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect on retained earnings, net of tax			$ 28,944