OTHER INCOME, NET (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
OTHER INCOME, NET
Foreign exchange (losses) gains	$ (4,675)	$ (8,942)	$ 8,004
Settlement with MRV Communications			481
Tax reversal for expiration of the statute of limitations	1,499
Other	203	777	1,323
Total	$ (2,973)	$ (8,165)	$ 9,808
Ownership interest in Fiberxon (as a percent)	8.00%
Period after the filing of the tax return when tax reserve was released	5 years

The aggregate foreign currency transaction gain (loss) (both realized and unrealized) included in determining net income for the reporting period. Excludes foreign currency transactions designated as hedges of net investment in a foreign entity and intercompany foreign currency transactions that are of a long-term nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements. For certain enterprises, primarily banks, that are dealers in foreign exchange, foreign currency transaction gains (losses) may be disclosed as dealer gains (losses).

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