Leases - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) Property
Leases [Line Items]
Weighted average discount rate	3.00%	3.00%
Weighted average remaining lease term	14 years 2 months 12 days	15 years
Operating cash flows used for operating leases	$ 18.0	$ 13.0
Tenant improvement allowance receipts	5.0	$ 10.3
Gain loss on sale lease back			$ 6.8
Proceeds received on sale lease back transactions			$ 41.2
2021 lease payment	24.0
Tenant improvement allowance	$ 1.3
Boulder, Colorado [Member]
Leases [Line Items]
Number of properties sold as part of sale and leaseback transactions \| Property			2
Portland, Oregon [Member]
Leases [Line Items]
Number of properties sold as part of sale and leaseback transactions \| Property			3

Leases.

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Number of properties sold as part of sale and leaseback transactions.

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Tenant improvements allowance receipts.

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Net cash outflow or inflow from monetary allowance granted by the landlord to a tenant to entice tenant to move into landlords building which will enable the tenant to prepare the leased premises for tenants occupancy.

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Amount of gain (loss) on sale and leaseback transaction from transfer of asset accounted for as sale.

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Amount of cash inflow after closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in investing activities.

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