Notes Payable (Interest Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Total interest incurred	$ 65,182	$ 44,332	$ 42,767
Interest capitalized	(11,219)	(4,902)	(9,243)
Total interest expense	$ 53,963	$ 39,430	$ 33,524