12. Fair Value Measurements
Recurring Fair Value Disclosures. The following table presents information about our financial instruments measured at fair value on a recurring basis as of December 31, 2020 and 2019 using the inputs and fair value hierarchy discussed in Note 2, “Summary of Significant Accounting Policies and Recent Accounting Pronouncements”:
Financial Instruments Measured at Fair Value on a Recurring Basis
 December 31, 2020December 31, 2019
 (in millions)Quoted 
Prices in
Active Markets
for Identical
Assets (Level 1)
Significant
Other
Observable
Inputs 
(Level 2)
Significant
Unobservable
Inputs
(Level 3)
TotalQuoted
 Prices in
Active Markets
for Identical
Assets (Level 1)
Significant
Other
Observable
Inputs
 (Level 2)
Significant
Unobservable
Inputs
(Level 3)
Total
Other Assets
Deferred compensation plan investments (1)
$129.8 $— $— $129.8 $151.8 $— $— $151.8 

(1)Approximately $37.8 million and $18.0 million of participant cash was withdrawn from our deferred compensation plan investments during the years ended December 31, 2020 and 2019, respectively.
Nonrecurring Fair Value Disclosures. The nonrecurring fair value disclosures inputs under the fair value hierarchy are discussed in Note 2, “Summary of Significant Accounting Policies and Recent Accounting Pronouncements.” We had no asset acquisitions of operating properties during the year ended December 31, 2020 and four asset acquisitions of operating properties during the year ended December 31, 2019. We recorded the real estate assets and identifiable above and below market and in-place leases at their relative fair values based upon methods similar to those used by independent appraisers of income producing properties. The fair value measurements associated with the valuation of these acquired assets represent Level 3 measurements within the fair value hierarchy. See Note 7, "Acquisitions and Dispositions" for a further discussion about these acquisitions.
Financial Instrument Fair Value Disclosures. The following table presents the carrying and estimated fair values of our notes payable at December 31, 2020 and 2019, in accordance with the policies discussed in Note 2, "Summary of Significant Accounting Policies and Recent Accounting Pronouncements."
 
 December 31, 2020December 31, 2019
(in millions)Carrying
Value
Estimated
Fair Value
Carrying
Value
Estimated
Fair Value
Fixed rate notes payable$3,126.9 $3,519.9 $2,380.4 $2,533.5 
Floating rate notes payable (1)
39.7 40.0 143.7 143.8 
(1)Includes balances outstanding under our unsecured credit facility at December 31, 2019.

Historical Timeline

Fiscal YearFiled
2020Feb 18, 2021Showing above
2019Feb 20, 2020
2018Feb 15, 2019
2017Feb 16, 2018
2016Feb 13, 2017
2015Feb 19, 2016

About Fair Value Disclosures

Fair value disclosures classify all assets and liabilities measured at fair value into a three-level hierarchy: Level 1 (quoted market prices), Level 2 (observable inputs like yield curves), and Level 3 (unobservable inputs requiring management estimates). The proportion of Level 3 assets directly reflects how much of the balance sheet depends on internal models rather than market evidence.

Key signals: a growing Level 3 balance relative to total fair-value assets increases valuation uncertainty and earnings volatility risk. Watch for transfers between levels — assets moving from Level 2 to Level 3 often signal deteriorating market liquidity. Unrealized gains and losses on Level 3 positions flow through earnings or other comprehensive income, so large swings deserve scrutiny. For financial institutions, examine the sensitivity disclosures that show how Level 3 valuations change under alternative assumptions. Compare the fair value of debt against its carrying amount to gauge hidden leverage.