| Cover | May 08, 2024 |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | May 08, 2024 |
| Current Fiscal Year End Date | --12-31 |
| Entity File Number | 001-41023 |
| Entity Registrant Name | NEW PROVIDENCE ACQUISITION CORP. II |
| Entity Central Index Key | 0001837929 |
| Entity Tax Identification Number | 86-1433401 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 10900 Research Blvd |
| Entity Address, Address Line Two | Suite 160C |
| Entity Address, Address Line Three | PMB 1081 |
| Entity Address, City or Town | Austin |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 78759 |
| City Area Code | 561 |
| Local Phone Number | 231-7070 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | false |
| Units, each consisting of one share of Class A common stock, $0.0001 par value, and one-third of one redeemable warrant | |
| Title of 12(b) Security | Units, each consisting of one share of Class A common stock, $0.0001 par value, and one-third of one redeemable warrant |
| Trading Symbol | NPABU |
| Security Exchange Name | NASDAQ |
| Class A common stock included as part of the units | |
| Title of 12(b) Security | Class A common stock included as part of the units |
| Trading Symbol | NPAB |
| Security Exchange Name | NASDAQ |
| Warrants included as part of the units, each whole warrant exercisable for one share of Class A common stock at an exercise price of $11.50 | |
| Title of 12(b) Security | Warrants included as part of the units, each whole warrant exercisable for one share of Class A common stock at an exercise price of $11.50 |
| Trading Symbol | NPABW |
| Security Exchange Name | NASDAQ |
