Long-Term Debt Long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Debt Disclosure [Abstract]
Prime rate borrowings	$ 1,400	$ 0
LIBOR borrowings	27,000	20,000
Revolving credit facility borrowings, total	28,400	20,000
Senior unsecured notes	30,000	30,000
Term loans	1,945	6,973
Long-term debt	60,345	56,973
Less current portion	1,428	5,837
Long-term debt	$ 58,917	$ 51,136

Amounts due on short-term bank loans secured by customers' securities on the balance sheet date.

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Amount borrowed under the credit facility as of the balance sheet date.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Sum of the carrying values as of the balance sheet date of the portions of all long-term notes and loans payable due within one year or the operating cycle if longer.

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Definite liabilities to third parties under a termination loan agreement, whether or not guaranteed in whole or in part by the government.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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