Equity method investment - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Mar. 31, 2018
Schedule of Equity Method Investments [Line Items]
Technology, trade name and customer relationship intangibles	$ 39,349,000		$ 39,349,000		$ 46,161,000
Amortization of Intangible Assets	2,430,000	$ 2,616,000	7,012,000	$ 7,973,000
Dividends received from equity method investment			49,940,000	33,651,000
Bankers Healthcare Group, LLC
Schedule of Equity Method Investments [Line Items]
Technology, trade name and customer relationship intangibles	9,200,000		9,200,000		$ 10,700,000
Amortization of Intangible Assets	475,000	693,000	1,400,000	2,100,000
Accretion income	630,000	719,000	2,000,000.0	2,200,000
Dividends received from equity method investment	9,000,000.0	$ 10,200,000	49,900,000	$ 33,700,000
Loan face amount	$ 0		$ 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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- Definition

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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