Note 9 - Equity-method Investment (Tables)

6 Months Ended

Jun. 30, 2016

Consolidated Statement of Operations [Member]

Notes Tables

Equity Method Investments [Table Text Block]

	Three Months Ended June 30,				Six Months Ended June 30,
	2016		2015		2016		2015
Asset impairments to write investment down to fair value	$	3,498	$	4,130	$	6,996	$	8,260
Our portion of the partnership’s operating losses		2,065		1,733		4,131		3,465
Non-cash interest expense related to the amortization of the discounted fair value of future equity contributions		62		183		154		394
Tax benefits and credits generated		6,837		7,652		12,782		14,902

Consolidated Balance Sheet [Member]

Notes Tables

Equity Method Investments [Table Text Block]

	June 30, 2016		December 31, 2015
Carrying value, recorded as a component of other non-current assets	$	11,157	$	22,284
Present value of obligation associated with future equity contributions, recorded as a component of accrued liabilities and other long-term liabilities		11,317		22,511