You may check CBP web site for detail.
<cig^B{nX -]hk2Q0 http://www.cbp.gov my1FW,3 U0X,g(2' The following is mentioned in U.S. Customs and Border Protection Declaration Form
k9Pwf"m|]( gs/ i%O Money And Other Monetary
g_8A1lt Instruments
zH)M,+P You may bring into or take out of the country, including
qK=uSLo\+ by mail, as much money as you wish. However, if
nev@ykP6 it is more than $10,000, you will need to report it to
{"e)Jj_= CBP. Ask the CBP officer for the Currency Reporting
4zo^ b0v Form (FinCen 105). The penalties for non-compliance
t_ju[xL5B can be severe.
kn5X:@{ “Money” means monetary instruments and includes U.S.
76 ]X or foreign coins currently in circulation, currency, travelers’
d-%bRGo/ checks in any form, money orders, and negotiable
k{Ad(S4J& instruments or investment securities in bearer form.