FAIR VALUE MEASUREMENTS - Fair Value Measurements (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Assets:
Cash and cash equivalents	$ 18,001	$ 31,324
Short-term investments	460	503
Total assets	18,461	31,827
Liabilities:
Contingent consideration	16,559	18,511
Total liabilities	16,559	18,511
Level 1 Inputs
Assets:
Cash and cash equivalents	18,001	31,324
Short-term investments	460	503
Total assets	18,461	31,827
Liabilities:
Contingent consideration	0	0
Total liabilities	0	0
Level 2 Inputs
Assets:
Cash and cash equivalents	0	0
Short-term investments	0	0
Total assets	0	0
Liabilities:
Contingent consideration	0	0
Total liabilities	0	0
Level 3 Inputs
Assets:
Cash and cash equivalents	0	0
Short-term investments	0	0
Total assets	0	0
Liabilities:
Contingent consideration	16,559	18,511
Total liabilities	$ 16,559	$ 18,511