Debt - Lines Of Credit (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Line of Credit Facility [Line Items]
Credit line capacity	$ 197,231,000
Balance Outstanding	$ 109,694,000	$ 114,664,000
JPMorgan Chase
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	4.01%
Credit line capacity	$ 175,000,000
Balance Outstanding	$ 105,028,000	104,152,000
Itau Bank
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	5.50%
Credit line capacity	$ 1,810,000
Balance Outstanding	$ 1,202,000	446,000
Bank of Chile
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	6.60%
Credit line capacity	$ 3,800,000
Balance Outstanding	$ 489,000	1,598,000
BICE Bank
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	5.50%
Credit line capacity	$ 2,500,000
Balance Outstanding	$ 543,000	1,819,000
BBVA Bank
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	5.50%
Credit line capacity	$ 3,250,000
Balance Outstanding	$ 554,000	1,665,000
Security Bank
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	5.50%
Credit line capacity	$ 27,000
Balance Outstanding	$ 27,000	501,000
Estado Bank
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	5.50%
Credit line capacity	$ 3,500,000
Balance Outstanding	$ 1,020,000	2,111,000
Santander Bank
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	5.50%
Credit line capacity	$ 4,500,000
Balance Outstanding	$ 708,000	1,988,000
Scotiabank
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	5.00%
Credit line capacity	$ 1,800,000
Balance Outstanding	$ 0	384,000
Banco De Sabadell
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	1.45%
Credit line capacity	$ 348,000
Balance Outstanding	$ 0	0
Banco Bilbao Vizcaya
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	2.45%
Credit line capacity	$ 348,000
Balance Outstanding	$ 0	0
Banco Santander
Line of Credit Facility [Line Items]
Interest rate on borrowings at September 30, 2018	2.20%
Credit line capacity	$ 348,000
Balance Outstanding	$ 123,000	$ 0