Note 6 - Stockholders' Equity (Details Textual) $ / shares in Units, $ in Thousands		3 Months Ended			9 Months Ended
	Jan. 02, 2019 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) shares	Mar. 31, 2019 USD ($) shares	Mar. 31, 2018 USD ($) shares	Sep. 30, 2019 USD ($) $ / shares shares	Sep. 30, 2018 USD ($)	Dec. 31, 2018 shares	Nov. 06, 2016 USD ($)	Mar. 31, 2006 shares	Nov. 30, 2004 shares	Mar. 31, 2004 shares
Capital Units, Authorized		245,000,000			245,000,000
Common Stock, Shares Authorized		200,000,000			200,000,000		200,000,000
Preferred Stock, Shares Authorized		20,000,000			20,000,000
Common Stock, Voting Rights, Votes Per Share		1			1
Dividends, Common Stock, Total | $					$ 0	$ 0
Treasury Stock, Value, Acquired, Cost Method | $		$ 11,000		$ 20,000
Stock Issued During Period, Value, Employee Benefit Plan | $			$ 4,000
Common Stock, Capital Shares Reserved for Future Issuance		6,163,624			6,163,624
Common Stock [Member]
Treasury Stock, Shares, Acquired		(0)		(0)
Treasury Stock, Value, Acquired, Cost Method | $		$ (0)		$ (0)
Stock Issued During Period, Shares, Employee Benefit Plan			196,509		196,509
Stock Issued During Period, Value, Employee Benefit Plan | $			$ 4,000		$ 4,000
November 2004 Authorization [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased										2,000,000
March 2004 Authorization [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased											2,000,000
The 2004-2006 Repurchase Authorization [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased									5
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased		279,200			279,200
The 2016 Repurchase Authorization [Member]
Stock Repurchase Program, Authorized Amount | $								$ 75,000
Treasury Stock, Shares, Acquired					651,593
Treasury Stock Acquired, Average Cost Per Share | $ / shares					$ 16.37
Treasury Stock, Value, Acquired, Cost Method | $					$ 11,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount | $		$ 39,000			$ 39,000
Raycom [Member]
Payments of Stock Issuance Costs | $	$ 100
Raycom [Member] | Common Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	11,500,000
Shares Issued, Price Per Share | $ / shares	$ 14.74
Common Class A [Member]
Common Stock, Shares Authorized		25,000,000			25,000,000		25,000,000
Common Stock, Voting Rights, Votes Per Share		10			10
Common Stock, Capital Shares Reserved for Future Issuance		1,503,254			1,503,254
Common Class A [Member] | Common Stock [Member]
Treasury Stock, Shares, Acquired		(0)		(0)
Treasury Stock, Value, Acquired, Cost Method | $		$ (0)		$ (0)
Stock Issued During Period, Shares, Employee Benefit Plan			0
Stock Issued During Period, Value, Employee Benefit Plan | $			$ 0