Label	Element	Value
Money Market Funds [Member]
Cash and Cash Equivalents, Fair Value Disclosure	us-gaap_CashAndCashEquivalentsFairValueDisclosure	$ 73,005,000
Cash and Cash Equivalents, Fair Value Disclosure	us-gaap_CashAndCashEquivalentsFairValueDisclosure	662,275,000
Cash and Cash Equivalents, at Carrying Value	us-gaap_CashAndCashEquivalentsAtCarryingValue	662,300,000
Cash and Cash Equivalents, at Carrying Value	us-gaap_CashAndCashEquivalentsAtCarryingValue	73,000,000.0
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and Cash Equivalents, Fair Value Disclosure	us-gaap_CashAndCashEquivalentsFairValueDisclosure	0
Cash and Cash Equivalents, Fair Value Disclosure	us-gaap_CashAndCashEquivalentsFairValueDisclosure	0
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and Cash Equivalents, Fair Value Disclosure	us-gaap_CashAndCashEquivalentsFairValueDisclosure	662,275,000
Cash and Cash Equivalents, Fair Value Disclosure	us-gaap_CashAndCashEquivalentsFairValueDisclosure	73,005,000
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and Cash Equivalents, Fair Value Disclosure	us-gaap_CashAndCashEquivalentsFairValueDisclosure	0
Cash and Cash Equivalents, Fair Value Disclosure	us-gaap_CashAndCashEquivalentsFairValueDisclosure	$ 0