You may check CBP web site for detail.
H\G{3.T.9 cT'w= http://www.cbp.gov IazkdJX~ *l>0t]5YH The following is mentioned in U.S. Customs and Border Protection Declaration Form
%3=J*wj>D ;vp\YIeX1 Money And Other Monetary
n9hm790x- Instruments
TD,nIgH` You may bring into or take out of the country, including
^toAw8A=@0 by mail, as much money as you wish. However, if
w|Aqqe it is more than $10,000, you will need to report it to
*\XH+/]+ CBP. Ask the CBP officer for the Currency Reporting
f3PMVf:< Form (FinCen 105). The penalties for non-compliance
%c/^_. can be severe.
rT7^-B* “Money” means monetary instruments and includes U.S.
.BZVX=x or foreign coins currently in circulation, currency, travelers’
m(47s checks in any form, money orders, and negotiable
@Hjea1@t instruments or investment securities in bearer form.