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

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Summary of Significant Accounting Policies - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle
Impact to Retained Earnings		$ 696,429	$ 585,304	$ 498,047	$ 417,945
Lease right-of-use assets		94,727	84,073
Operating lease liability		97,162	$ 86,713
Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle
Impact to Retained Earnings		$ (515)
Cumulative Effect, Period of Adoption, Adjustment [Member] \| ASU 2016-13
New Accounting Pronouncements or Change in Accounting Principle
Impact to Retained Earnings	$ 500
Adjustments \| ASU 2016-13
New Accounting Pronouncements or Change in Accounting Principle
Increase in Allowance for Credit Losses	700
Increase to Deferred Tax Assets	$ 200