The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

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- Definition

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- Definition

Value of investments transferred from the entity's investments in noncash transactions.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Number of Investments

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- Definition

The largest investment which the entity has made in a single fund.

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Trading Security, Fair Value

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Investment Securities - Fair Value of Hedge Funds Subject to Restrictions on Redemption Frequency (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) fund	Dec. 31, 2019 USD ($)
Investment securities
Number of investments \| fund		14
Private equity funds
Investment securities
Trading security, fair value		$ 121.2
Total private equity funds and hedge funds included in other long-term investments
Investment securities
Other long-term investments largest single investment		29.1	$ 54.6
Trading security, fair value		121.2	161.1
Fair value unfunded commitments		45.7	50.2
Private equity funds \| Private equity funds
Investment securities
Trading security, fair value		121.2	106.5
Fair value unfunded commitments		45.7	50.2
Private equity funds \| Aerospace/Defense/Government
Investment securities
Trading security, fair value		69.1	33.8
Fair value unfunded commitments		15.3	23.3
Private equity funds \| Manufacturing/Industrial
Investment securities
Trading security, fair value		28.6	57.7
Fair value unfunded commitments		0.0	4.1
Private equity funds \| Financial services
Investment securities
Trading security, fair value		23.5	15.0
Fair value unfunded commitments		30.4	22.8
Hedge funds \| Hedge funds
Investment securities
Transfer from investments	$ 45.6
Trading security, fair value		0.0	54.6
Fair value unfunded commitments		0.0	0.0
Hedge funds \| Long/short banks and financial
Investment securities
Trading security, fair value		0.0	54.6
Fair value unfunded commitments		$ 0.0	$ 0.0