Significant Accounting Policies - Additional Cash Flow Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Accounting Policies [Abstract]
Cash paid for interest	$ 8,069	$ 9,719
Cash paid for income taxes	0	0
Unsettled securities transactions	78,769	21,957
Right-of-use lease assets obtained in exchange for lessee operating lease liabilities	4,013	1,326
Treasury stock issued to 401(k) stock purchase plan	$ 0	$ 1,749

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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The increase (decrease) during the reporting period in the aggregate amount of obligations incurred arising from transactions with broker-dealers, such as amounts due on margin and unsettled cash transactions; includes payables to brokers, dealers and clearing organizations.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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Value of treasury shares or units reissued. Excludes reissuance of shares or units in treasury for award under share-based payment arrangement.

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