Unaudited Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Unaudited Consolidated Statements of Cash Flows [Abstract]
Net cash provided by operating activities	$ 10,674	$ 9,160
Investing activities:
Purchases of available-for-sale investments	(126,146)	(104,263)
Proceeds from sales or maturities of available-for-sale investments	104,555	108,087
Net purchases of short-term investments	(3)	(203)
Other investing activities	(244)	(2,808)
Net cash provided by (used in) investing activities	(21,838)	813
Financing activities:
Dividends paid to shareholders	(3,776)us-gaap_PaymentsOfDividendsCommonStock	(3,753)us-gaap_PaymentsOfDividendsCommonStock
Net cash used in financing activities	(3,776)	(3,753)
Effect of foreign exchange rates on cash and cash equivalents	(779)	(501)
Increase (decrease) in cash and cash equivalents	(15,719)	5,719
Cash and cash equivalents at beginning of period	64,632	59,297
Cash and cash equivalents at end of period	$ 48,913	$ 65,016

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.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the 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. Includes effect from exchange rate changes.

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The net cash outflow or inflow from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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Cash outflow for purchase of trading, available-for-sale securities and held-to-maturity securities.

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The cash outflow for securities or other assets acquired, which qualify for treatment as an investing activity and are to be liquidated, if necessary, within the current operating cycle. Includes cash flows from securities classified as trading securities that were acquired for reasons other than sale in the short-term.

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