Equity method investment - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Technology, trade name and customer relationship intangibles	$ 48,610,000		$ 51,130,000
Amortization of Intangible Assets	2,520,000	$ 2,311,000
Dividends received from equity method investment	7,957,000	12,666,000
Bankers Healthcare Group, LLC
Schedule of Equity Method Investments [Line Items]
Technology, trade name and customer relationship intangibles	8,500,000		$ 8,800,000
Amortization of Intangible Assets	293,000	475,000
Accretion income	564,000	683,000
Dividends received from equity method investment	8,000,000.0	12,700,000
Loan face amount	$ 0	$ 0

Accretion of discount into income

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Face (par) amount of debt instrument at time of issuance.

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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