Summary of Significant Accounting Policies (Narrative) (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Right-of-use asset	$ 11,694
Lease liabilities	$ 12,373
Adjustments for New Accounting Principle, Early Adoption [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Right-of-use asset		$ 11,900
Accrued Rent		686
Lease liabilities		$ 12,600

Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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