Subsequent Events (Narrative) (Details) $ in Thousands, $ in Millions		3 Months Ended		12 Months Ended
	Mar. 06, 2020 USD ($)	Mar. 31, 2020 USD ($)		Dec. 31, 2019 USD ($)		Mar. 31, 2020 AUD ($)
Subsequent Event [Line Items]
Contractual facility		$ 276,053		$ 283,138
Bank Of America Credit Facility [Member]
Subsequent Event [Line Items]
Contractual facility	$ 55,000	55,000		55,000
Bank Of America Line Of Credit [Member]
Subsequent Event [Line Items]
Contractual facility	$ 5,000	5,000		5,000
NAB Corporate Loan Facility [Member]
Subsequent Event [Line Items]
Contractual facility		$ 73,668	[1]	$ 84,360	[2]
Line of credit facility, maximum borrowing capacity						$ 120.0

[1] The contractual facilities and outstanding balances of the foreign currency denominated borrowings were translated into U.S. dollars based on the applicable exchange rates as of March 31, 2020.

[2] The contractual facilities and outstanding balances of the foreign currency denominated borrowings were translated into U.S. dollars based on the applicable exchange rates as of December 31, 2019.