SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS Prior Period Balance Sheet Adjustments, Adoption of ASU 2014-09 (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Condensed Consolidated Balance Sheet Data
Accounts Receivable, Net, Current	$ 15,046	$ 6,528
Prepaid expenses and other current assets	16,770	8,715
DEFERRED TAX ASSETS	19,857	11,342
Deferred Income, Current		0
Other accrued liabilities	3,409	2,734
Retained earnings	$ 350,393	332,891
As Reported
Condensed Consolidated Balance Sheet Data
Accounts Receivable, Net, Current		6,961
Prepaid expenses and other current assets		8,520
DEFERRED TAX ASSETS		12,032
Deferred Income, Current		16,207
Other accrued liabilities		2,434
Retained earnings		317,912
Adjustments for Accounting Standards Update 2014-09 [Member]
Condensed Consolidated Balance Sheet Data
Accounts Receivable, Net, Current		(433)
Prepaid expenses and other current assets		195
DEFERRED TAX ASSETS		(690)
Deferred Income, Current		(16,207)
Other accrued liabilities		300
Retained earnings		$ 14,979