|
Fair Value Measurements (Company's Portfolio of Other Investments Measured Using Net Asset Valuations) (Details) (USD $)
In Thousands, unless otherwise specified |
Mar. 31, 2013
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|---|---|
| Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] | |
| Fair Value | $ 577,783 |
| Unfunded Commitments | 122,194 |
|
Private equity partnerships [Member]
|
|
| Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] | |
| Fair Value | 345,666 |
| Unfunded Commitments | 84,958 |
|
Senior secured bank loan funds [Member]
|
|
| Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] | |
| Fair Value | 204,114 |
| Unfunded Commitments | 17,506 |
|
Hedge funds [Member]
|
|
| Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] | |
| Fair Value | 5,219 |
| Unfunded Commitments | 0 |
|
Miscellaneous other investments [Member]
|
|
| Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] | |
| Fair Value | 22,784 |
| Unfunded Commitments | $ 19,730 |