CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 14,919us-gaap_ProfitLoss	$ 6,746us-gaap_ProfitLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	8,390	8,324
Stock-based compensation expenses	2,198us-gaap_ShareBasedCompensation	2,193us-gaap_ShareBasedCompensation
Other adjustments	(3,531)us-gaap_OtherNoncashIncomeExpense	(1,771)us-gaap_OtherNoncashIncomeExpense
Change in operating assets and liabilities:
Accounts receivable, trade	11,854	15,401
Inventories	(7,939)us-gaap_IncreaseDecreaseInInventories	(4,834)us-gaap_IncreaseDecreaseInInventories
Accounts payable	1,207	1,372
Changes in other operating assets and liabilities	3,077	(9,006)
Net cash provided by operating activities	30,175	18,425
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds from the sale of property and equipment	461	150
Additions to property and equipment	(23,076)	(4,247)
Purchases of short-term investments	(114)	(14,876)
Sales of short-term and long-term investments	12,658	19,546
Net cash provided by (used in) investing activities	(10,071)	573
CASH FLOWS FROM FINANCING ACTIVITIES
Borrowing from banks	26,408us-gaap_ProceedsFromBankDebt	20,333us-gaap_ProceedsFromBankDebt
Repayments to banks	(15,183)us-gaap_RepaymentsOfBankDebt	(15,468)us-gaap_RepaymentsOfBankDebt
Purchase of non-controlling interests	(413)	(234)
Purchases of treasury stock	0	(5,593)
Issuance of common stock	1,573	2,138
Net cash provided by financing activities	12,385	1,176
Effect of foreign currency translation on cash	(14,910)	1,173
Net increase in cash and cash equivalents	17,579	21,347
Cash and cash equivalents at beginning of period	128,537	133,733
Cash and cash equivalents at end of period	146,116	155,080
Cash paid for interest	151us-gaap_InterestPaid	168us-gaap_InterestPaid
Cash paid for taxes	$ 8,211us-gaap_IncomeTaxesPaid	$ 7,379us-gaap_IncomeTaxesPaid

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.