Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 262,483	$ 37,458
Other current assets	4,047	3,483
Total current assets	266,530	40,941
Investments in affiliates		107,950
Deferred tax assets	109,884	115,285
Other assets	28	55
Total assets	376,442	264,231
Current liabilities:
Accrued employment costs	1,533	2,356
Income taxes payable	42,719
Other current liabilities	2,360	3,772
Total current liabilities	46,612	6,128
Pension and other postretirement liabilities	18,001	18,433
Long-term liabilities	70,354	69,259
Total liabilities	134,967	93,820
Commitments and contingencies
Shareholders' Equity:
Preferred stock, 0.01 par value; 10,000,000 shares authorized, no shares issued and outstanding
Common Stock:
Paid-in capital	1,019,988	1,019,988
Accumulated deficit	(752,537)	(826,460)
Accumulated other comprehensive loss	(16,695)	(13,836)
Total shareholders' equity	241,475	170,411
Total liabilities and shareholders' equity	376,442	264,231
Voting Common Stock [Member]
Common Stock:
Common stock, 0.01 par value	216	216
Treasury stock (at cost), 154,494 shares of voting common stock	(9,592)	(9,592)
Nonvoting Common Stock [Member]
Common Stock:
Common stock, 0.01 par value	$ 95	$ 95