STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Details Textual)					1 Months Ended	3 Months Ended	12 Months Ended
	May 31, 2018 USD ($) $ / shares shares	Feb. 09, 2018 USD ($) $ / shares shares	Apr. 11, 2017 USD ($)	Jun. 30, 2015 $ / shares	Mar. 31, 2019	Jun. 30, 2017 shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) fiscal_quarter $ / shares shares	Dec. 31, 2016 shares	Dec. 31, 2015 shares	Dec. 31, 2014 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period								3 years
Stock-Based Compensation Amortization | $							$ 426,000	$ 723,000
Preferred Stock Dividend Rate Percentage Additional Shares							8.00%
Preferred dividends per share (in dollars per share) | $ / shares							$ (0.26)	$ (0.26)
Preferred Stock Redemption Premium, Amortization Period							5 years
Deemed Dividend on Redeemable Convertible Preferred Stock | $							$ 3,493,000	$ 2,716,000
Preferred Stock Optional Redemption Percentage							15.00%
Convertible Preferred Stock, Term of Conversion, Ratio Used to Determine Conversion Price							2.25
Payments for purchase of treasury stock | $							$ 0	$ 338,000
Certificate of Designation Restrictive Covenants, Judgment Threshold | $							$ 2,000,000
Options granted (in shares)							110,979	116,830
Exercise price of shares granted (in dollars per share) | $ / shares							$ 2.42	$ 1.13
Forfeitures in period (in shares)								0
Shares outstanding							1,102,627	1,055,497	938,667
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares							932,994
Warrant or right, outstanding							2,600,000
Cash dividends on Series B redeemable convertible preferred stock | $							$ (2,548,000)	$ (2,140,000)
Preferred Stock Dividends, Income Statement Impact | $							$ 1,188,000	$ 0
Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance							2,700,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized							3,300,000
Stock Incentive Plan 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period							3 years	3 years
Fair per share granted (in dollars per share) | $ / shares								$ 0.70
Options granted (in shares)							110,979	116,830
Exercise price of shares granted (in dollars per share) | $ / shares								$ 1.13
Forfeitures in period (in shares)							63,849	0
Share-based compensation cost not yet recognized | $							$ 500,000
Period of recognition							1 year 7 months 18 days
2014 Non-Employee Director Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred Compensation Arrangement with Individual, Shares Authorized for Issuance											300,000
Deferred Compensation Arrangement with Individual, Annual Grant of Restricted Common Stock, Value | $							$ 20,000
SRE Monarch [Member] | Series B-2 Purchase Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reimbursement of expenses | $			$ 300,000
JPMorgan Chase Funding Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant, authorized issuance		600,000
Warrant, period		2 years
Warrant, exercise price per share (in USD per share) | $ / shares		$ 2.25
Common Class B1, B2 and B3 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Predetermined Lapse Internal One in Transfer Restriction Term							6 months
Predetermined Lapse Internal Two in Transfer Restriction Term							9 months
Predetermined Lapse Internal Three in Transfer Restriction Term							12 months
Length of Period After Initial Public Offering in Conversion Term							5 months
Threshold Percentage of Offering Price in Initial Public Offering in Conversion Term (Greater than 125%)							125.00%
Length of Period to Reach Threshold Percentage of Offering Price in Initial Public Offering in Conversion Term							20 days
Common Class B1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Class C Common Stock Conversion Percentage (in percentage)							25.00%
Common Class B2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Class C Common Stock Conversion Percentage (in percentage)							25.00%
Common Class B3 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Class C Common Stock Conversion Percentage (in percentage)							50.00%
Common Class B4 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Length of Period After Initial Public Offering in Conversion Term							4 years
Convertible conversion rate							1
Threshold Book Value of Entity in Transfer Restriction Term | $							$ 730,400,000
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion of Stock, Shares Issued							8,200,000
Series B-1 and B-2 Cumulative Convertible Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Redeemable convertible preferred stock, shares issued											8,200,000
Convertible Preferred Stock, Shares Issued upon Conversion							8,200,000
Deemed dividend on redeemable convertible preferred stock | $											$ 26,400,000
Preferred distribution rate							8.00%
Preferred stock redemption price							150.00%
Preferred stock, liquidation preference, percent							150.00%
Preferred stock, value, issued | $							$ 26,400,000	$ 8,000,000
Preferred stock, redemption amount | $							39,600,000	11,600,000
Preferred Stock Redemption Premium | $							13,200,000	3,600,000
Cash dividends on Series B redeemable convertible preferred stock | $							$ (2,139,000)	$ (2,140,000)
Series B-3 Cumulative Convertible Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated Fair Value per Share | $ / shares							$ 4.12
Preferred distribution rate		5.65%					5.65%
Preferred dividends per share (in dollars per share) | $ / shares								$ (0.17)
Preferred stock redemption price							145.00%
Preferred stock, liquidation preference, percent							145.00%
Cash dividends on Series B redeemable convertible preferred stock | $							$ (409,000)
Series B-3 Cumulative Convertible Preferred Stock [Member] | JPMorgan Chase Funding Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Redeemable convertible preferred stock, shares issued		2,352,941
Series B-1 Cumulative Convertible Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Redeemable convertible preferred stock, par value (in dollars per share) | $ / shares		$ 0.01
Series B Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred Stock, Redemption, Minimum Percentage of Share Holders							85.00%
Preferred stock redemption price							150.00%
Preferred Stock, Redemption Notice							30 days
Threshold of Gross Proceeds of Underwritten Public Offering in Conversion Terms | $							$ 75,000,000
Preferred Stock, Vote on As-Converted, Minimum Percent of Original Issue							50.00%
Preferred Stock, Trigger for Redemption, Number of Quarters Dividends Not Paid in Full | fiscal_quarter								2
Preferred Stock, Redemption Period After Trigger for Redemption								180 days
Covenant, maximum excess of certain expenses over approved budget, percent							103.00%
Covenant, excess of certain expenses over approved budget, percent, actual							103.00%
Series B Preferred Stock [Member] | JPMorgan Chase Funding Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price of stock issued (in usd per share) | $ / shares		$ 3.40
Preferred stock, purchase price, value | $		$ 8,000,000
Series A Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred distribution rate							7.50%
Cash dividends on Series B redeemable convertible preferred stock | $							$ (1,188,000)
Series A Preferred Stock [Member] | JPMorgan Chase Funding Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Redeemable convertible preferred stock, shares issued	22,000
Estimated Fair Value per Share | $ / shares							$ 1,000
Preferred distribution rate	7.50%
Redeemable convertible preferred stock, par value (in dollars per share) | $ / shares	$ 0.01
Price of stock issued (in usd per share) | $ / shares	$ 1,000
Preferred stock, purchase price, value | $	$ 22,000,000
Common Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Special Dividends Payable Amount Per Share (in dollars per share) | $ / shares							$ 0.95
Special Dividends, Share Holding Period							12 months
Common Class B [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Threshold Amount of New Equity Securities Issued in Conversion Term | $							$ 50,000,000
Threshold Maturity Term of New Indebtedness in Conversion Term							1 year
Common Class C [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum Percentage Of Net Proceeds Used In Pro Rata Redemption (in percentage)							30.00%
Maximum Net Proceeds Used In Pro Rata Redemption | $							$ 50,000,000
Relinquishment of Class C common stock to treasury							44,068
Common Class D [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Length of Period After Initial Public Offering in Conversion Term							12 months
Length of Period Prior to Representation Submitted by Shareholder in Conversion Term							90 years
Conversion of Stock, Shares Issued							1
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeitures in period							0	0
Vesting period								3 years
Shares, Granted							249,496	469,097
Stock-based compensation (in shares)								22,279
Treasury stock purchase (in shares)								196,278
Payments for purchase of treasury stock | $								$ 300,000
Stock Repurchased During Period, Value | $								$ 200,000
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number							523,754	791,510	889,456
Stock-based compensation expense | $								$ 100,000
Shares authorized for issuance								425,453
Restricted Stock [Member] | Stock Incentive Plan 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Approved but unissued restricted common stock									86,207
Forfeitures in period									9,942
Shares Paid for Tax Withholding for Share Based Compensation									3,137
Restricted Stock [Member] | 2014 Non-Employee Director Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Granted								116,772
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value | $ / shares				$ 1.74			$ 2.67	$ 1.13
Restricted Stock [Member] | Certain Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Granted							114,865	262,309
Restricted Stock [Member] | Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Granted										850,000
Restricted Stock [Member] | Chief Financial Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period								3 years
Shares, Granted						100,000		50,000
Shares issued net of tax withholdings								79,324
Share-based Compensation Award, Tranche One [Member] | Restricted Stock [Member] | 2014 Non-Employee Director Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Vested								45,976
Share-based Compensation Award, Tranche Two [Member] | Restricted Stock [Member] | 2014 Non-Employee Director Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Vested								70,796
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation (in shares)						73,128	517,252	527,383
Common Stock [Member] | 2014 Non-Employee Director Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation (in shares)							74,136
Common Stock [Member] | Share-based Compensation Award, Tranche One [Member] | 2014 Non-Employee Director Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation (in shares)							44,132
Fair per share granted (in dollars per share) | $ / shares							$ 1.81
Common Stock [Member] | Share-based Compensation Award, Tranche Two [Member] | 2014 Non-Employee Director Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation (in shares)							30,004
Fair per share granted (in dollars per share) | $ / shares							$ 2.67
Subsequent Event [Member] | Series B-1 and B-2 Cumulative Convertible Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock redemption price					160.00%
$1.81 Exercise Price [Member] | Stock Incentive Plan 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation (in shares)							30,000
Fair per share granted (in dollars per share) | $ / shares							$ 0.73
Exercise price of shares granted (in dollars per share) | $ / shares							$ 1.81
$2.65 Exercise Price [Member] | Stock Incentive Plan 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation (in shares)							80,979
Fair per share granted (in dollars per share) | $ / shares							$ 1.06
Exercise price of shares granted (in dollars per share) | $ / shares							$ 2.65
DRD Gross-Up Distribution [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash dividends on Series B redeemable convertible preferred stock | $							$ (200,000)