Fair value measurements - Schedule of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	$ 1,106,786	$ 1,062,824
Insurance Solutions \| Variable Interest Entity, Primary Beneficiary
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	120,680	125,898
Insurance Solutions \| Consolidated Balance Including Variable Interest Entity
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	1,077,488	1,041,454
Other than Fair Value Measurement \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	126,711	123,579
Other than Fair Value Measurement \| Insurance Solutions \| Variable Interest Entity, Primary Beneficiary
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	127,620	132,194
Other than Fair Value Measurement \| Insurance Solutions \| Consolidated Balance Including Variable Interest Entity
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	254,331	255,773
Mark to Fair Value \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	(1,534)	(7,902)
Mark to Fair Value \| Insurance Solutions \| Variable Interest Entity, Primary Beneficiary
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	(7,889)	(6,296)
Mark to Fair Value \| Insurance Solutions \| Consolidated Balance Including Variable Interest Entity
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	(9,423)	(14,198)
Fair value \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	125,177	115,677
Fair value \| Insurance Solutions \| Variable Interest Entity, Primary Beneficiary
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	119,731	125,898
Fair value \| Insurance Solutions \| Consolidated Balance Including Variable Interest Entity
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	244,908	241,575
Corporate loans \| Variable Interest Entity, Primary Beneficiary
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	119,731	125,757
Corporate loans \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	124,067	114,735
Corporate loans \| Other than Fair Value Measurement \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	125,422	117,823
Corporate loans \| Mark to Fair Value \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	(1,355)	(3,089)
Corporate loans \| Fair value \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	124,067	114,734
Other invested assets \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	23,084	21,317
Other invested assets \| Other than Fair Value Measurement \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	1,289	5,756
Other invested assets \| Mark to Fair Value \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Unpaid Principal Balance	(179)	(4,813)
Other invested assets \| Fair value \| Insurance Solutions
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Investments	$ 1,110	$ 943

Mount Logan Capital Inc. 10-K