Investment in Unconsolidated Entities - Cash Received and Distributions (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
NewINK Joint Venture
Schedule of Equity Method Investments [Line Items]
Cash generated from other activities and excess cash	$ 0	$ 1,182	$ 411	$ 2,775
Total	0	1,182	411	2,775
Inland Joint Venture
Schedule of Equity Method Investments [Line Items]
Cash generated from other activities and excess cash	250	200	250	1,450
Total	$ 250	$ 200	$ 250	$ 1,450

Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration