Short-Term and Long-Term Debt (Credit Facilities) (Details) - 12 months ended Dec. 31, 2017 |
USD ($) |
JPY (¥) |
JPY (¥) |
|---|---|---|---|
| Prudential Financial and Prudential Funding | |||
| CreditFacility [Line Items] | |||
| Original Term | 5 years | 5 years | |
| Expiration Date | Jul. 17, 2022 | Jul. 17, 2022 | |
| Capacity | $ | $ 4,000,000,000 | ||
| Amount Outstanding | $ | $ 0 | ||
| Prudential Holdings of Japan | |||
| CreditFacility [Line Items] | |||
| Original Term | 3 years | 3 years | |
| Expiration Date | Sep. 30, 2019 | Sep. 30, 2019 | |
| Capacity | ¥ | ¥ 100,000,000,000 | ||
| Amount Outstanding | ¥ | ¥ 0 |