Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current Assets:
Receivables, allowance for doubtful accounts	$ 699	$ 523
Property and Equipment, accumulated depreciation	302,901	285,322
Capitalized Software, accumulated amortization	$ 340,864	$ 303,540
SEI Investments shareholders' equity:
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	750,000	750,000
Common stock, shares issued	157,405	159,031
Common stock, shares outstanding	157,405	159,031

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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