PORT PREFERRED STOCK - Schedule (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Roll Forward]
Balance	$ 309,122	$ 277,388	$ 293,964
Balance	$ 302,152	$ 262,521	$ 302,152
Preferred Stock | Preferred Class A
Class of Stock [Line Items]
Issuance of common stock (in shares)		15,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Roll Forward]
Balance		$ 14,909
Dividends Available Upon Redemption		590
Dividends Paid		(365)
Balance		$ 15,134
Preferred Stock | Preferred Class B
Class of Stock [Line Items]
Issuance of common stock (in shares)		125
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Roll Forward]
Balance		$ 99
Dividends Available Upon Redemption		7
Dividends Paid		(7)
Balance		$ 99