CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Accumulated Other Comprehensive (Loss) Income	Accumulated Deficit	Total
Balance at Dec. 31, 2014	$ 1,360,668	$ 124	$ (919,577)	$ 441,215
Balance (in shares) at Dec. 31, 2014	300,100,000
Increase (Decrease) in Shareholders' Equity
Stock-based compensation (note 9)	$ 754			754
Shares issued for the settlement of accounts payable (note 8)	$ 443			443
Shares issued for settlement of accounts payable (note 8) (in shares)	430,000
Unrealized gain (loss) on available-for-sale securities, net of taxes (note 2)		(647)		(647)
Net income			(8,095)	(8,095)
Balance at Jun. 30, 2015	$ 1,361,865	(523)	(927,672)	433,670
Balance (in shares) at Jun. 30, 2015	300,530,000
Balance at Dec. 31, 2014	$ 1,360,668	124	(919,577)	441,215
Balance (in shares) at Dec. 31, 2014	300,100,000
Increase (Decrease) in Shareholders' Equity
Share repurchase (note 8)				$ (1,800)
Share repurchase (note 8) (in shares)				(1,896,442)
Balance at Dec. 31, 2015	$ 1,359,144	(825)	(940,027)	$ 418,292
Balance (in shares) at Dec. 31, 2015	298,634,000
Increase (Decrease) in Shareholders' Equity
Stock-based compensation (note 9)	$ 491			491
Return of capital distribution (note 8)	(1,491)			(1,491)
Exercise of stock options (note 9)	$ 1,873			1,873
Exercise of stock options (note 9) (in shares)	812,000
Share repurchase (note 8)	$ (582)			$ (582)
Share repurchase (note 8) (in shares)	(558,000)			(557,991)
Other-than-temporary impairment on marketable equity securities (note 2)		882		$ 882
Unrealized gain (loss) on available-for-sale securities, net of taxes (note 2)		1,500		1,500
Net income			21,338	21,338
Balance at Jun. 30, 2016	$ 1,359,435	$ 1,557	$ (918,689)	$ 442,303
Balance (in shares) at Jun. 30, 2016	298,888,000