Note 4 - NewWave Acquisition - Allocation of Purchase Price Consideration (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	May 01, 2017
Goodwill, Ending Balance	$ 172,129	$ 172,129
New Wave [Member]
Cash and cash equivalents			$ 12,220
Accounts receivable			15,027
Prepaid and other current assets			2,286
Property, plant and equipment			192,234
Intangible assets			476,300
Other noncurrent assets			1,184
Total Assets Acquired			699,251
Accounts payable and accrued liabilities			25,125
Deferred revenue			14,516
Deferred income taxes			6,644
Total Liabilities Assumed			46,285
Net Assets Acquired			652,966
Purchase price consideration			740,166
Goodwill, Ending Balance			$ 87,200