Related Party Transactions (Affiliated Notes Receivable) (Details) - Affiliated Entity - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Total notes receivable - affiliated	$ 3,171	$ 37,192
U.S. dollar floating rate notes
Related Party Transaction [Line Items]
Total notes receivable - affiliated	$ 0	34,008
U.S. dollar floating rate notes | Minimum
Related Party Transaction [Line Items]
Interest Rates	4.02%
U.S. dollar floating rate notes | Maximum
Related Party Transaction [Line Items]
Interest Rates	4.23%
U.S. dollar fixed rate notes
Related Party Transaction [Line Items]
Total notes receivable - affiliated	$ 3,171	$ 3,184
U.S. dollar fixed rate notes | Minimum
Related Party Transaction [Line Items]
Interest Rates	8.15%
U.S. dollar fixed rate notes | Maximum
Related Party Transaction [Line Items]
Interest Rates	14.85%