Travel documents are intended a being passports or any other internationally recognized identity card. Tourists may remain in Croatia for up to three months.
Citizens of the European Union are not required to have a visa when entering the Republic of Croatia.
Aliens not requiring visas for entering the Republic of Croatia may sojourn in the Republic of Croatia for up to 90 days over a 6 month period, including the first entry. 
A complete list of Visa Regime Regulations is available on the Ministry of Foreign Affairs and European Integration web site: www.mvpei.hr