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Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Millions |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Aug. 07, 2018 | Feb. 09, 2015 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2017 | Nov. 17, 2016
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Deferred rent |  |  | $ 2.4 | $ 2.1 |  |  |
Total rent expense |  |  | 14.9 | $ 14.8 | $ 15.2 |  |
Exposure to earthquake loss | $ 68.3 |  |  |  |  |  |
Gain contingency, unrecorded amount |  |  | $ 31.6 |  |  |  |
California DOI [Member] |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Penalty interest assessed, statutory rate |  |  |  |  |  |  | 7.00%
Litigation settlement expense |  | $ 27.6 |  |  |  |  |
Other liabilities [Member] |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Gain contingency, unrecorded amount |  |  |  |  |  | $ 30.9 |

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- Definition The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707 + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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