NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES: (Details 5) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Restricted cash
Restricted cash to be held, related to removal of analog equipment	$ 200,000	$ 200,000
Restricted cash classified as noncurrent		58,500,000
Rollforward of the allowance for doubtful accounts
Balance at beginning of period	3,008,000	3,242,000	2,932,000
Charged to expense	1,141,000	751,000	703,000
Net write-offs	(1,058,000)	(985,000)	(393,000)
Balance at end of period	$ 3,091,000	$ 3,008,000	$ 3,242,000
Four Points
Restricted cash
Deposit in escrow account as a percentage of purchase price		10.00%
Freedom
Restricted cash
Deposit in escrow account as a percentage of purchase price		10.00%