EQUITY AND CHANGES IN OTHER COMPREHENSIVE INCOME (LOSS) - Equity (Details) $ / shares in Units, $ in Thousands				6 Months Ended
	Jun. 26, 2018 $ / shares	Apr. 17, 2018	Mar. 20, 2018 $ / shares	Jun. 30, 2018 USD ($) shares	Dec. 31, 2017 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Class of Stock [Line Items]
Total equity				$ 144,642	$ 134,780	$ 132,232	$ 127,090
Common stock, dividends, declared (in dollars per share) | $ / shares	$ 0.14		$ 0.12
Stock split, conversion ratio		1.1
Preferred Stock
Class of Stock [Line Items]
Total equity				$ 9,195	15,971	19,828	20,000
Conversion of stock, shares converted (in shares) | shares				6,776
Common Stock
Class of Stock [Line Items]
Total equity				$ 996	$ 830	$ 786	$ 715
Shares issued upon conversion (in shares) | shares				847,023
PDL LLC | Corporate Joint Venture
Class of Stock [Line Items]
Ownership percentage				51.00%
Other ownership interests, contributed capital				$ 1,200