Fair Value Measurements - Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financial assets:
Trading securities	$ 214,146	$ 65,717
Available for sale securities	673,706	925,535
Level 1
Financial assets:
Trading securities	21,807	39
Available for sale securities	17,409	13,762
Investment in SWS common stock		70,282
Financial liabilities:
Securities sold, not yet purchased	27,648
Level 2
Financial assets:
Trading securities	192,338	65,678
Available for sale securities	656,297	911,773
Loans held for sale	1,434,955	1,263,135
Derivative assets	35,676	23,805
Financial liabilities:
Securities sold, not yet purchased	102,396	48
Derivative liabilities	5,426	12,849
Level 3
Financial assets:
Trading securities	1
Loans held for sale	25,880	9,017
Mortgage servicing asset	52,285	36,155
Recurring
Financial assets:
Trading securities	214,146	65,717
Available for sale securities	673,706	925,535
Loans held for sale	1,460,835	1,272,152
Derivative assets	35,676	23,805
Mortgage servicing asset	52,285	36,155
Investment in SWS common stock		70,282
Financial liabilities:
Securities sold, not yet purchased	130,044	48
Derivative liabilities	$ 5,426	$ 12,849

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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