Recent Accounting Pronouncements	6 Months Ended
Jun. 30, 2018
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recently adopted accounting pronouncements: In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU 2014-09, Revenue from Customers. ASU 2014-09 clarifies the principles for recognizing revenue. While insurance contracts are not within the scope of this updated guidance, the Company’s insurance service fee revenue and non-insurance business revenue are subject to this updated guidance. The updated guidance requires an entity to recognize revenue as performance obligations are met, in order to reflect the transfer of promised goods or services to customers in an amount that reflects the consideration the entity is entitled to receive for those goods or services. The updated guidance, as amended by ASU 2015-14, was effective for public business entities for annual and interim reporting periods beginning after December 15, 2017. The Company adopted this guidance on January 1, 2018 on a prospective basis. The impact of applying this guidance prospectively was a cumulative effect adjustment that increased retained earnings, a component of stockholders' equity, by $1 million after-tax. In January 2016, the FASB issued ASU 2016-01, Financial Instruments. ASU 2016-01 amends the accounting guidance for financial instruments to require all equity investments with readily determinable fair values to be measured at fair value with changes in the fair value recognized in net income (other than those accounted for under equity method of accounting or those that result in consolidation of the investee). The updated guidance was effective for public business entities for annual reporting periods beginning after December 15, 2017 and interim periods within those years. The Company adopted this updated guidance on January 1, 2018 on a prospective basis. The impact of applying this guidance prospectively was a cumulative effect adjustment that increased retained earnings and decreased accumulated other comprehensive income ("AOCI") by offsetting amounts of $291 million, resulting in no net impact to total stockholders' equity. Following the adoption, the Company reports changes in fair value related to equity securities within net realized and unrealized gains on investments. In February 2018, the FASB issued ASU 2018-02, Reporting Comprehensive Income, which amends previous guidance to allow a reclassification to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act of 2017 (the “Tax Act”). The amount of the reclassification includes the effect of the change in the U.S. federal corporate income tax rate on the gross deferred tax amounts and related valuation allowances, if any, at the date of the enactment of the Tax Act related to items in AOCI. The updated guidance will be effective for reporting periods beginning after December 15, 2018, and is eligible for early adoption. The Company adopted this updated guidance on January 1, 2018. The impact of applying this guidance was a cumulative effect adjustment that decreased retained earnings and increased AOCI by offsetting amounts of $76 million, resulting in no net impact to total stockholders' equity. All other accounting and reporting standards that have become effective in 2018 were either not applicable to the Company or their adoption did not have a material impact on the Company. Accounting and reporting standards that are not yet effective: In February 2016, the FASB issued ASU 2016-02, Leases, which amends the accounting and disclosure guidance for leases. This guidance retains the two classifications of a lease, as either an operating or finance lease, both of which will require lessees to recognize a right-of-use asset and a lease liability for leases with terms of more than 12 months. The right-of-use asset and the lease liability will be determined based upon the present value of cash flows. Finance leases will reflect the financial arrangement by recognizing interest expense on the lease liability separately from the amortization expense of the right-of-use asset. Operating leases will recognize lease expense (with no separate recognition of interest expense) on a straight-line basis over the term of the lease. The accounting by lessors is not significantly changed by the updated guidance. The updated guidance is effective for reporting periods beginning after December 15, 2018, and can be adopted prospectively or will require that the earliest comparative period presented include the measurement and recognition of existing leases with an adjustment to equity as if the updated guidance had always been applied. The Company is currently evaluating the impact that the adoption of this guidance will have on its results of operations, financial position and liquidity. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses, which amends the accounting guidance for credit losses on financial instruments. The updated guidance amends the current other-than-temporary impairment model for available-for-sale debt securities by requiring the recognition of impairments relating to credit losses through an allowance account and limits the amount of credit loss to the difference between a security’s amortized cost basis and its fair value. This guidance also applies a new current expected credit loss model for determining credit-related impairments for financial instruments measured at amortized cost. The updated guidance is effective for reporting periods beginning after December 15, 2019. The Company will not be able to determine the impact the adoption of this guidance will have on its results of operations, financial position or liquidity until the year the guidance becomes effective. All other recently issued but not yet effective accounting and reporting standards are either not applicable to the Company or are not expected to have a material impact on the Company.

Recent Accounting Pronouncements

Recently adopted accounting pronouncements:

In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU 2014-09, Revenue from Customers. ASU 2014-09 clarifies the principles for recognizing revenue. While insurance contracts are not within the scope of this updated guidance, the Company’s insurance service fee revenue and non-insurance business revenue are subject to this updated guidance. The updated guidance requires an entity to recognize revenue as performance obligations are met, in order to reflect the transfer of promised goods or services to customers in an amount that reflects the consideration the entity is entitled to receive for those goods or services. The updated guidance, as amended by ASU 2015-14, was effective for public business entities for annual and interim reporting periods beginning after December 15, 2017. The Company adopted this guidance on January 1, 2018 on a prospective basis. The impact of applying this guidance prospectively was a cumulative effect adjustment that increased retained earnings, a component of stockholders' equity, by $1 million after-tax.

In January 2016, the FASB issued ASU 2016-01, Financial Instruments. ASU 2016-01 amends the accounting guidance for financial instruments to require all equity investments with readily determinable fair values to be measured at fair value with changes in the fair value recognized in net income (other than those accounted for under equity method of accounting or those that result in consolidation of the investee). The updated guidance was effective for public business entities for annual reporting periods beginning after December 15, 2017 and interim periods within those years. The Company adopted this updated guidance on January 1, 2018 on a prospective basis. The impact of applying this guidance prospectively was a cumulative effect adjustment that increased retained earnings and decreased accumulated other comprehensive income ("AOCI") by offsetting amounts of $291 million, resulting in no net impact to total stockholders' equity. Following the adoption, the Company reports changes in fair value related to equity securities within net realized and unrealized gains on investments.

In February 2018, the FASB issued ASU 2018-02, Reporting Comprehensive Income, which amends previous guidance to allow a reclassification to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act of 2017 (the “Tax Act”). The amount of the reclassification includes the effect of the change in the U.S. federal corporate income tax rate on the gross deferred tax amounts and related valuation allowances, if any, at the date of the enactment of the Tax Act related to items in AOCI. The updated guidance will be effective for reporting periods beginning after December 15, 2018, and is eligible for early adoption. The Company adopted this updated guidance on January 1, 2018. The impact of applying this guidance was a cumulative effect adjustment that decreased retained earnings and increased AOCI by offsetting amounts of $76 million, resulting in no net impact to total stockholders' equity.

All other accounting and reporting standards that have become effective in 2018 were either not applicable to the Company or their adoption did not have a material impact on the Company.

Accounting and reporting standards that are not yet effective:

In February 2016, the FASB issued ASU 2016-02, Leases, which amends the accounting and disclosure guidance for leases. This guidance retains the two classifications of a lease, as either an operating or finance lease, both of which will require lessees to recognize a right-of-use asset and a lease liability for leases with terms of more than 12 months. The right-of-use asset and the lease liability will be determined based upon the present value of cash flows. Finance leases will reflect the financial arrangement by recognizing interest expense on the lease liability separately from the amortization expense of the right-of-use asset. Operating leases will recognize lease expense (with no separate recognition of interest expense) on a straight-line basis over the term of the lease. The accounting by lessors is not significantly changed by the updated guidance. The updated guidance is effective for reporting periods beginning after December 15, 2018, and can be adopted prospectively or will require that the earliest comparative period presented include the measurement and recognition of existing leases with an adjustment to equity as if the updated guidance had always been applied. The Company is currently evaluating the impact that the adoption of this guidance will have on its results of operations, financial position and liquidity.

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses, which amends the accounting guidance for credit losses on financial instruments. The updated guidance amends the current other-than-temporary impairment model for available-for-sale debt securities by requiring the recognition of impairments relating to credit losses through an allowance account and limits the amount of credit loss to the difference between a security’s amortized cost basis and its fair value. This guidance also applies a new current expected credit loss model for determining credit-related impairments for financial instruments measured at amortized cost. The updated guidance is effective for reporting periods beginning after December 15, 2019. The Company will not be able to determine the impact the adoption of this guidance will have on its results of operations, financial position or liquidity until the year the guidance becomes effective.

All other recently issued but not yet effective accounting and reporting standards are either not applicable to the Company or are not expected to have a material impact on the Company.