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v3.19.3.a.u2

Debt (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 USD ($) Period $ / shares shares | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | May 31, 2019 USD ($)
Debt Instrument [Line Items] |  |  |  |
FHLBC advances | $ 155,000,000.0 |  |  |
FHLBC fixed interest rate | 1.91% |  |  |
Collateral, principal balance of FHLB (as a percent) | 102.00% |  |  |
Interest paid | $ 50,800,000 | $ 51,300,000 | $ 57,800,000 |
Senior Notes | 5.75% Senior Notes due 2023 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate (in hundredths) | 5.75% |  |  |
Redemption price, percentage (in hundredths) | 100.00% |  |  |
Ownership percentage threshold for declaration of due and payable | 25.00% |  |  |
Convertible Junior Subordinated Debentures, at 9% per annum, Due 2063 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate (in hundredths) | 9.00% |  |  |
Redemption price, percentage (in hundredths) | 100.00% |  |  |
Conversion rate (in shares per $1,000 note) | shares | 74.4718 |  |  |
Principal amount of notes used in determining conversion rate | $ 1,000 |  |  |
Initial conversion price (in dollars per share) | $ / shares | $ 13.43 |  |  |
Period preceding election to convert | 5 days |  |  |
Convertible debt, number of equity instruments reserved for conversion (in shares) | shares | 19,100,000 |  |  |
Closing sale price of our common stock for consideration of redemption (in dollars per share) | $ / shares | $ 17.46 |  |  |
Minimum number of trading days | 20 days |  |  |
Maximum number of trading days | 30 days |  |  |
Minimum number of consecutive interest periods for which interest payments may be deferred | Period | 1 |  |  |
Maximum period for which interest payments may be deferred without giving rise to an event of default | 10 years |  |  |
Period in which reasonable commercial efforts must begin, maximum | 1 day |  |  |
Anniversary payment release of the start of the interest deferral to the Alternative Payment Mechanism in lieu of the final maturity of the debentures | 10 years |  |  |
Net proceeds cap (in hundredths) | 2.00% |  |  |
Maximum number of shares of common stock issuable under the Alternative Payment Mechanism (in shares) | shares | 10,000,000 |  |  |
Maximum percentage of aggregate principal amount of the debentures (in hundredths) | 25.00% |  |  |
Revolving Credit Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  | $ 175,000,000

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- Definition We cannot pay deferred interest other than from the net proceeds of Alternative Payment Mechanism sales, except at the final maturity of the debentures or at the tenth anniversary of the start of the interest deferral. + References No definition available. + Details
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