Clearfield, Inc. Quarterly report [Sections 13 or 15(d)]

Quarterly report [Sections 13 or 15(d)]

Note 5 - Fair Value Measurements - Fair Value Measurements (Details)

Note 5 - Fair Value Measurements - Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Sep. 30, 2025
Cash equivalents	$ 2,155	$ 15,761
Investment securities:	137,669	144,306
Fair Value, Inputs, Level 1 [Member]
Cash equivalents	2,155	15,761
Investment securities:	0	0
Fair Value, Inputs, Level 2 [Member]
Cash equivalents	0	0
Investment securities:	137,669	144,306
Fair Value, Inputs, Level 3 [Member]
Cash equivalents	0	0
Investment securities:	0	0
Money Market Funds [Member]
Cash equivalents	2,155	15,761
Money Market Funds [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash equivalents	2,155	15,761
Money Market Funds [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash equivalents	0	0
Money Market Funds [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash equivalents	0	0
US Treasury Securities [Member]
Investment securities:	137,423	144,063
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities:	0	0
US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities:	137,423	144,063
US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities:	0	0
Certificates of Deposit [Member]
Investment securities:	246	243
Certificates of Deposit [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities:	0	0
Certificates of Deposit [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities:	246	243
Certificates of Deposit [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities:	$ 0	$ 0

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ Details