FAIR VALUE MEASUREMENTS - Fair value on a recurring basis (Details) - Recurring Basis - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Carrying Value
Other long-term assets:
Money market mutual funds	$ 605	$ 132
Total assets at fair value	7,821	19,641
Carrying Value \| Mutual Fund Large U.S. Equity
Other long-term assets:
Equity securities, available-for-sale:	1,995	2,057
Carrying Value \| Mutual Fund Small/Mid U.S. Equity
Other long-term assets:
Equity securities, available-for-sale:	2,683	2,222
Carrying Value \| Mutual Fund International
Other long-term assets:
Equity securities, available-for-sale:	675	833
Carrying Value \| Mutual Fund Balanced
Other long-term assets:
Equity securities, available-for-sale:	520	747
Carrying Value \| Mutual Fund Fixed Income
Other long-term assets:
Equity securities, available-for-sale:	1,343	750
Carrying Value \| Real D Inc. \| Common Stock
Other long-term assets:
Equity securities, available-for-sale:		12,900
Quoted Prices in Active Market (Level 1)
Other long-term assets:
Money market mutual funds	605	132
Total assets at fair value	7,821	19,641
Quoted Prices in Active Market (Level 1) \| Mutual Fund Large U.S. Equity
Other long-term assets:
Equity securities, available-for-sale:	1,995	2,057
Quoted Prices in Active Market (Level 1) \| Mutual Fund Small/Mid U.S. Equity
Other long-term assets:
Equity securities, available-for-sale:	2,683	2,222
Quoted Prices in Active Market (Level 1) \| Mutual Fund International
Other long-term assets:
Equity securities, available-for-sale:	675	833
Quoted Prices in Active Market (Level 1) \| Mutual Fund Balanced
Other long-term assets:
Equity securities, available-for-sale:	520	747
Quoted Prices in Active Market (Level 1) \| Mutual Fund Fixed Income
Other long-term assets:
Equity securities, available-for-sale:	$ 1,343	750
Quoted Prices in Active Market (Level 1) \| Real D Inc. \| Common Stock
Other long-term assets:
Equity securities, available-for-sale:		$ 12,900