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Investments (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2020
Investments |
Fixed Maturities and Equity Securities Available-for-Sale (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | Allowance | ​ | ​ | ​
​ | ​ | ​ | Amortized | ​ | unrealized | ​ | unrealized | ​ | for credit | ​ | ​ | ​
​ |  | ​ | cost (1) |  | gains |  | losses |  | loss |  | Fair value
​ | ​ | ​ | (in millions)
March 31, 2020 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Fixed maturities, available-for-sale: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. government and agencies | ​ | $ | ​ | 1,463.6 | ​ | $ | 267.6 | ​ | $ | — | ​ | $ | — | ​ | $ | 1,731.2
Non-U.S. governments | ​ | ​ | ​ | 837.4 | ​ | ​ | 120.9 | ​ | ​ | 1.6 | ​ | ​ | — | ​ | ​ | 956.7
States and political subdivisions | ​ | ​ | ​ | 7,077.8 | ​ | ​ | 709.6 | ​ | ​ | 24.0 | ​ | ​ | — | ​ | ​ | 7,763.4
Corporate | ​ | ​ | ​ | 38,044.9 | ​ | ​ | 2,446.8 | ​ | ​ | 1,063.5 | ​ | ​ | 7.0 | ​ | ​ | 39,421.2
Residential mortgage-backed pass-through securities | ​ | ​ | ​ | 3,063.8 | ​ | ​ | 138.4 | ​ | ​ | 0.3 | ​ | ​ | — | ​ | ​ | 3,201.9
Commercial mortgage-backed securities | ​ | ​ | ​ | 4,793.6 | ​ | ​ | 20.7 | ​ | ​ | 320.2 | ​ | ​ | 0.4 | ​ | ​ | 4,493.7
Collateralized debt obligations (2) | ​ | ​ | ​ | 3,555.6 | ​ | ​ | 3.9 | ​ | ​ | 211.1 | ​ | ​ | 0.1 | ​ | ​ | 3,348.3
Other debt obligations | ​ | ​ | ​ | 7,812.0 | ​ | ​ | 172.1 | ​ | ​ | 192.6 | ​ | ​ | 0.1 | ​ | ​ | 7,791.4
Total fixed maturities, available-for-sale | ​ | $ | ​ | 66,648.7 | ​ | $ | 3,880.0 | ​ | $ | 1,813.3 | ​ | $ | 7.6 | ​ | $ | 68,707.8
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Other-than-
​ | ​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​ | ​ | temporary
​ | ​ | Amortized | ​ | ​ | unrealized | ​ | unrealized | ​ | ​ | ​ | ​ | impairments
​ | ​ | cost | ​ | ​ | gains | ​ | losses | ​ | Fair value | ​ | in OCI (3)
​ | ​ | ​ | ​ | (in millions)
December 31, 2019 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Fixed maturities, available-for-sale: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. government and agencies | ​ | $ | 1,627.0 | ​ | $ | ​ | 100.2 | ​ | $ | 3.0 | ​ | $ | 1,724.2 | ​ | $ | —
Non-U.S. governments | ​ | ​ | 852.3 | ​ | ​ | ​ | 144.1 | ​ | ​ | 0.2 | ​ | ​ | 996.2 | ​ | ​ | —
States and political subdivisions | ​ | ​ | 6,857.1 | ​ | ​ | ​ | 644.5 | ​ | ​ | 11.6 | ​ | ​ | 7,490.0 | ​ | ​ | —
Corporate | ​ | ​ | 36,993.1 | ​ | ​ | ​ | 3,706.5 | ​ | ​ | 52.2 | ​ | ​ | 40,647.4 | ​ | ​ | —
Residential mortgage-backed pass-through securities | ​ | ​ | 2,913.9 | ​ | ​ | ​ | 72.3 | ​ | ​ | 3.8 | ​ | ​ | 2,982.4 | ​ | ​ | —
Commercial mortgage-backed securities | ​ | ​ | 4,746.6 | ​ | ​ | ​ | 127.6 | ​ | ​ | 24.0 | ​ | ​ | 4,850.2 | ​ | ​ | 15.8
Collateralized debt obligations (2) | ​ | ​ | 3,226.7 | ​ | ​ | ​ | 2.9 | ​ | ​ | 14.3 | ​ | ​ | 3,215.3 | ​ | ​ | 0.9
Other debt obligations | ​ | ​ | 8,085.8 | ​ | ​ | ​ | 129.6 | ​ | ​ | 14.9 | ​ | ​ | 8,200.5 | ​ | ​ | 31.7
Total fixed maturities, available-for-sale | ​ | $ | 65,302.5 | ​ | $ | ​ | 4,927.7 | ​ | $ | 124.0 | ​ | $ | 70,106.2 | ​ | $ | 48.4
(1) | Amortized cost excludes accrued interest receivable of $569.8 million as of March 31, 2020.
(2) | Primarily consists of collateralized loan obligations backed by secured corporate loans.
(3) | Excludes $62.3 million as of December 31, 2019, of net unrealized gains on impaired fixed maturities, available-for-sale related to changes in fair value subsequent to the impairment date, which are included in gross unrealized gains and gross unrealized losses.
Fixed Maturities Available-for-Sale by Contractual Maturity (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Amortized cost |  | Fair value
​ | ​ | (in millions)
Due in one year or less | ​ | $ | 2,170.7 | ​ | $ | 2,173.4
Due after one year through five years | ​ |  | 10,179.8 | ​ |  | 10,168.8
Due after five years through ten years | ​ |  | 12,378.6 | ​ |  | 12,459.7
Due after ten years | ​ |  | 22,694.6 | ​ |  | 25,070.6
Subtotal | ​ |  | 47,423.7 | ​ |  | 49,872.5
Mortgage-backed and other asset-backed securities | ​ |  | 19,225.0 | ​ |  | 18,835.3
Total | ​ | $ | 66,648.7 | ​ | $ | 68,707.8
​
Net Realized Capital Gains and Losses (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the three months ended
​ | ​ | March 31,
​ |  | 2020 |  | 2019
​ | ​ | (in millions)
Fixed maturities, available-for-sale: | ​ | ​ | ​ | ​ | ​ | ​
Gross gains | ​ | $ | 23.1 | ​ | $ | 2.5
Gross losses | ​ |  | (4.2) | ​ |  | (1.5)
Net credit losses (1) | ​ |  | (7.9) | ​ |  | (6.8)
Hedging, net (2) | ​ |  | (1.5) | ​ |  | —
Fixed maturities, trading (3) | ​ |  | (16.4) | ​ |  | 14.2
Equity securities (4) | ​ |  | (63.7) | ​ |  | 21.0
Mortgage loans | ​ |  | (15.7) | ​ |  | 0.3
Derivatives | ​ |  | 290.5 | ​ |  | 5.0
Other | ​ |  | (72.8) | ​ |  | 49.8
Net realized capital gains | ​ | $ | 131.4 | ​ | $ | 84.5
(1) | Upon adoption of authoritative guidance effective January 1, 2020, net credit losses include adjustments to the credit loss valuation allowance, write-offs and recoveries on available-for-sale securities. Prior to 2020, net credit losses included net other-than-temporary impairment losses and recoveries on available-for-sale securities.
(2) | The change in fair value of fixed maturities, available-for-sale and the change in fair value of derivative hedging instruments in fair value hedging relationships are reported in net investment income with the earnings effect of fixed maturities, available-for-sale.
(3) | Unrealized gains (losses) on fixed maturities, trading still held at the reporting date were $(14.2) million and $14.2 million for the three months ended March 31, 2020 and 2019, respectively.
(4) | Unrealized gains (losses) on equity securities still held at the reporting date were $(66.0) million and $19.8 million for the three months ended March 31, 2020 and 2019, respectively. This excludes $(38.5) million and $22.5 million of unrealized gains (losses) on equity securities still held at the reporting date for the three months ended March 31, 2020 and 2019, respectively, that were reported in net investment income.
Allowance for credit loss (Tables) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | For the three months ended March 31, 2020
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Residential | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | mortgage- | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | backed | ​ | Commercial | ​ | Collateralized | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | U.S. | ​ | ​ | ​ | ​ | States and | ​ | ​ | ​ | ​ | pass- | ​ | mortgage- | ​ | debt | ​ | Other | ​ | ​ | ​
​ | ​ | government | ​ | Non-U.S | ​ | political | ​ | ​ | ​ | ​ | through | ​ | backed | ​ | obligations | ​ | debt | ​ | ​ | ​
​ |  | and agencies |  | governments |  | subdivisions |  | Corporate |  | securities |  | securities |  | (2) |  | obligations |  | Total
​ | ​ | ​ | (in millions)
Beginning balance (1) |  | $ | — |  | $ | — |  | $ | — |  | $ | — | ​ | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | —
Additions for credit losses not previously recorded |  | ​ | — |  | ​ | — |  | ​ | — |  | ​ | 7.0 | ​ | ​ | — |  | ​ | 0.4 |  | ​ | 0.1 |  | ​ | 0.1 |  | ​ | 7.6
Ending balance |  | $ | — |  | $ | — |  | $ | — |  | $ | 7.0 | ​ | $ | — |  | $ | 0.4 |  | $ | 0.1 |  | $ | 0.1 |  | $ | 7.6
(1) | The allowance for credit loss associated with fixed maturities, available-for-sale was applied prospectively upon adoption of authoritative guidance effective January 1, 2020.
(2) | Primarily consists of collateralized loan obligations backed by secured corporate loans.
Other-Than-Temporary Impairment Losses, Net of Recoveries (Table) | ​
​ | ​ | ​ | ​
​ | ​ | For the three months ended
​ |  | March 31, 2019
​ | ​ | (in millions)
Net realized capital gains, excluding impairment losses on available-for-sale securities | ​ | $ | 91.3
Net other-than-temporary impairment losses on available-for-sale securities | ​ | ​ | (9.6)
Other-than-temporary impairment losses on fixed maturities, available-for-sale reclassified to other comprehensive income (1) | ​ |  | 2.8
Net impairment losses on available-for-sale securities | ​ | ​ | (6.8)
Net realized capital gains | ​ | $ | 84.5
(1) | Represents the net impact of (a) gains resulting from reclassification of noncredit impairment losses for fixed maturities with bifurcated OTTI from net realized capital gains (losses) to OCI and (b) losses resulting from reclassification of previously recognized noncredit impairment losses from OCI to net realized capital gains (losses) for fixed maturities with bifurcated OTTI that had additional credit losses or fixed maturities that previously had bifurcated OTTI that have now been sold or are intended to be sold.
Other-Than-Temporary Impairment, Credit Losses Recognized in Earnings (Table) | ​
​ | ​ | ​ | ​
​ | ​ | For the three months ended
​ |  | March 31, 2019
​ | ​ | (in millions)
Beginning balance | ​ | $ | (117.5)
Credit losses for which an other-than-temporary impairment was not previously recognized | ​ |  | (2.0)
Credit losses for which an other-than-temporary impairment was previously recognized | ​ |  | (4.3)
Reduction for credit losses previously recognized on fixed maturities now sold, paid down or intended to be sold | ​ |  | 20.4
Net reduction for positive changes in cash flows expected to be collected and amortization (1) | ​ |  | 1.1
Ending balance | ​ | $ | (102.3)
(1) | Amounts are recognized in net investment income.
Available-for-Sale Securities in Unrealized Loss Positions Without an Allowance for Credit Loss (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | March 31, 2020
​ | ​ | Less than | ​ | Greater than or | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | twelve months | ​ | equal to twelve months | ​ | Total
​ |  | ​ |  | Gross |  | ​ |  | Gross |  | ​ |  | Gross
​ | ​ | Fair | ​ | unrealized | ​ | Fair | ​ | unrealized | ​ | Fair | ​ | unrealized
​ | ​ | value | ​ | losses | ​ | value | ​ | losses | ​ | value | ​ | losses
​ | ​ | (in millions)
Fixed maturities, available-for-sale (1): | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Non-U.S. governments | ​ | $ | 115.4 | ​ | $ | 1.6 | ​ | $ | 5.2 | ​ | $ | — | ​ | $ | 120.6 | ​ | $ | 1.6
States and political subdivisions | ​ | ​ | 812.6 | ​ | ​ | 23.7 | ​ | ​ | 26.1 | ​ | ​ | 0.3 | ​ | ​ | 838.7 | ​ | ​ | 24.0
Corporate | ​ | ​ | 13,248.9 | ​ | ​ | 1,021.9 | ​ | ​ | 150.9 | ​ | ​ | 41.7 | ​ | ​ | 13,399.8 | ​ | ​ | 1,063.6
Residential mortgage-backed pass-through securities | ​ | ​ | 15.1 | ​ | ​ | 0.2 | ​ | ​ | 3.7 | ​ | ​ | 0.1 | ​ | ​ | 18.8 | ​ | ​ | 0.3
Commercial mortgage-backed securities | ​ | ​ | 3,691.3 | ​ | ​ | 302.2 | ​ | ​ | 161.8 | ​ | ​ | 15.5 | ​ | ​ | 3,853.1 | ​ | ​ | 317.7
Collateralized debt obligations (2) | ​ | ​ | 2,419.4 | ​ | ​ | 164.5 | ​ | ​ | 797.0 | ​ | ​ | 45.7 | ​ | ​ | 3,216.4 | ​ | ​ | 210.2
Other debt obligations | ​ | ​ | 4,598.9 | ​ | ​ | 185.4 | ​ | ​ | 82.9 | ​ | ​ | 7.2 | ​ | ​ | 4,681.8 | ​ | ​ | 192.6
Total fixed maturities, available-for-sale | ​ | $ | 24,901.6 | ​ | $ | 1,699.5 | ​ | $ | 1,227.6 | ​ | $ | 110.5 | ​ | $ | 26,129.2 | ​ | $ | 1,810.0
(1) | Fair value and gross unrealized losses are excluded for available-for-sale securities for which an allowance for credit loss has been recorded.
(2) | Primarily consists of collateralized loan obligations backed by secured corporate loans.
Gross Unrealized Losses for Fixed Maturities (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, 2019
​ | ​ | Less than | ​ | Greater than or | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | twelve months | ​ | equal to twelve months | ​ | Total
​ |  | ​ |  | Gross |  | ​ | ​ |  | Gross |  | ​ |  | Gross
​ | ​ | Fair | ​ | unrealized | ​ | Fair | ​ | unrealized | ​ | Fair | ​ | unrealized
​ | ​ | value | ​ | losses (2) | ​ | value | ​ | losses (2) | ​ | value | ​ | losses (2)
​ | ​ | (in millions)
Fixed maturities, available-for-sale: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. government and agencies | ​ | $ | 100.0 | ​ | $ | 1.9 | ​ | $ | 74.2 | ​ | $ | 1.1 | ​ | $ | 174.2 | ​ | $ | 3.0
Non-U.S. governments | ​ |  | 17.6 | ​ |  | 0.2 | ​ |  | 12.4 | ​ |  | — | ​ |  | 30.0 | ​ |  | 0.2
States and political subdivisions | ​ |  | 559.9 | ​ |  | 11.2 | ​ |  | 86.3 | ​ |  | 0.4 | ​ |  | 646.2 | ​ |  | 11.6
Corporate | ​ |  | 1,041.5 | ​ |  | 27.8 | ​ |  | 394.7 | ​ |  | 24.4 | ​ |  | 1,436.2 | ​ |  | 52.2
Residential mortgage-backed pass-through securities | ​ |  | 429.6 | ​ |  | 1.4 | ​ |  | 237.3 | ​ |  | 2.4 | ​ |  | 666.9 | ​ |  | 3.8
Commercial mortgage-backed securities | ​ |  | 829.3 | ​ |  | 9.2 | ​ |  | 268.5 | ​ |  | 14.8 | ​ |  | 1,097.8 | ​ |  | 24.0
Collateralized debt obligations (1) | ​ |  | 639.4 | ​ |  | 1.8 | ​ |  | 1,447.8 | ​ |  | 12.5 | ​ |  | 2,087.2 | ​ |  | 14.3
Other debt obligations | ​ |  | 1,772.8 | ​ |  | 9.5 | ​ |  | 613.7 | ​ |  | 5.4 | ​ |  | 2,386.5 | ​ |  | 14.9
Total fixed maturities, available-for-sale | ​ | $ | 5,390.1 | ​ | $ | 63.0 | ​ | $ | 3,134.9 | ​ | $ | 61.0 | ​ | $ | 8,525.0 | ​ | $ | 124.0
(1) Primarily consists of collateralized loan obligations backed by secured corporate loans.
(2) | Prior to the implementation of authoritative guidance in 2020, other than temporary impairment losses reported in OCI were included with gross unrealized losses resulting in total gross unrealized losses for fixed maturities, available-for-sale being reported in the table.
Net Unrealized Gains and Losses on Available-for-Sale Securities and Derivative Instruments (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | March 31, 2020 |  | December 31, 2019
​ | ​ | (in millions)
Net unrealized gains on fixed maturities, available-for-sale (1) | ​ | $ | 2,026.1 | ​ | $ | 4,834.2
Noncredit component of impairment losses on fixed maturities, available-for-sale (2) | ​ |  | — | ​ |  | (48.4)
Net unrealized gains on derivative instruments | ​ |  | 154.7 | ​ |  | 94.1
Adjustments for assumed changes in amortization patterns | ​ |  | 71.2 | ​ |  | (261.0)
Adjustments for assumed changes in policyholder liabilities | ​ |  | (470.1) | ​ |  | (1,133.5)
Net unrealized gains on other investments and noncontrolling interest adjustments | ​ |  | 69.6 | ​ |  | 96.8
Provision for deferred income taxes | ​ |  | (398.9) | ​ |  | (766.9)
Net unrealized gains on available-for-sale securities and derivative instruments | ​ | $ | 1,452.6 | ​ | $ | 2,815.3
(1) | Excludes net unrealized gains (losses) on fixed maturities, available-for-sale included in fair value hedging relationships.
(2) | Prior to the implementation of authoritative guidance in 2020, the noncredit component of impairment losses on fixed maturities, available-for-sale was included as a separate component of stockholders' equity.
Financing Receivable Credit Quality Indicators (Table) |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | 2020 |  | 2019 |  | 2018 |  | 2017 |  | 2016 |  | Prior |  | Total
​ | ​ | ​ | (in millions)
Commercial mortgage loans (1): | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |
A- and above |  | $ | 536.3 |  | $ | 2,593.6 |  | $ | 2,556.5 |  | $ | 2,006.5 |  | $ | 1,575.2 |  | $ | 4,680.4 |  | $ | 13,948.5
BBB+ thru BBB- |  | ​ | 12.4 |  | ​ | 165.2 |  | ​ | 322.5 |  | ​ | 182.0 |  | ​ | 76.0 |  | ​ | 398.4 |  | ​ | 1,156.5
BB+ thru BB- |  | ​ | — |  | ​ | 28.8 |  | ​ | 4.3 |  | ​ | — |  | ​ | — |  | ​ | — |  | ​ | 33.1
B+ and below |  | ​ | — |  | ​ | — |  | ​ | — |  | ​ | — |  | ​ | — |  | ​ | 4.5 |  | ​ | 4.5
Total |  | $ | 548.7 |  | $ | 2,787.6 |  | $ | 2,883.3 |  | $ | 2,188.5 |  | $ | 1,651.2 |  | $ | 5,083.3 |  | $ | 15,142.6
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Direct financing leases: |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​
A- and above |  | $ | 9.6 |  | $ | 1.4 |  | $ | 35.6 |  | $ | 16.0 |  | $ | 29.4 |  | $ | 233.4 |  | $ | 325.4
BBB+ thru BBB- |  | ​ | 40.3 |  | ​ | 22.3 |  | ​ | 38.4 |  | ​ | 23.8 |  | ​ | 16.7 |  | ​ | 157.6 |  | ​ | 299.1
BB+ thru BB- |  | ​ | 5.6 |  | ​ | 6.7 |  | ​ | 3.4 |  | ​ | — |  | ​ | — |  | ​ | 4.1 |  | ​ | 19.8
B+ and below |  | ​ | — |  | ​ | — |  | ​ | — |  | ​ | — |  | ​ | — |  | ​ | 1.3 |  | ​ | 1.3
Total |  | $ | 55.5 |  | $ | 30.4 |  | $ | 77.4 |  | $ | 39.8 |  | $ | 46.1 |  | $ | 396.4 |  | $ | 645.6
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Residential mortgage loans (1): |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​
Performing |  | $ | 73.6 |  | $ | 509.4 |  | $ | 210.5 |  | $ | 196.6 |  | $ | 138.2 |  | $ | 409.1 |  | $ | 1,537.4
Non-performing |  | ​ | — |  | ​ | 0.7 |  | ​ | 0.9 |  | ​ | 0.6 |  | ​ | — |  | ​ | 7.5 |  | ​ | 9.7
Total |  | $ | 73.6 |  | $ | 510.1 |  | $ | 211.4 |  | $ | 197.2 |  | $ | 138.2 |  | $ | 416.6 |  | $ | 1,547.1
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Reinsurance recoverables |  | ​ |  |  | ​ |  |  | ​ |  |  | ​ |  |  | ​ |  |  | ​ |  |  | $ | 510.4
(1) | The amortized cost of mortgage loans excluded accrued interest receivable of $56.0 million as of March 31, 2020.
Commercial Mortgage Loan Portfolio by Credit Risk (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, 2019 (1)
​ |  | Brick and mortar |  | CTL |  | Total
​ | ​ | (in millions)
A- and above | ​ | $ | 13,885.2 | ​ | $ | 76.7 | ​ | $ | 13,961.9
BBB+ thru BBB- | ​ |  | 943.1 | ​ |  | 83.8 | ​ |  | 1,026.9
BB+ thru BB- | ​ |  | 23.3 | ​ |  | — | ​ |  | 23.3
B+ and below | ​ |  | 5.1 | ​ |  | — | ​ |  | 5.1
Total | ​ | $ | 14,856.7 | ​ | $ | 160.5 | ​ | $ | 15,017.2
(1) | Prior to the implementation of authoritative guidance in 2020, commercial mortgage loan credit quality disclosures included information about classes of those mortgages and information by vintage was excluded. Beginning in 2020, we determined that total commercial mortgage loans by credit risk and vintage is the most meaningful presentation.
Performing and Non-Performing Residential Mortgage Loans (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, 2019 (1)
​ |  | First liens |  | Home equity |  | Total
​ | ​ | (in millions)
Performing | ​ | $ | 1,474.2 | ​ | $ | 8.0 | ​ | $ | 1,482.2
Non-performing | ​ |  | 11.5 | ​ |  | 3.0 | ​ |  | 14.5
Total | ​ | $ | 1,485.7 | ​ | $ | 11.0 | ​ | $ | 1,496.7
(1) | Prior to the implementation of authoritative guidance in 2020, residential mortgage loan credit quality disclosures included information about classes of those mortgages and information by vintage was excluded. Beginning in 2020, we determined that total residential mortgage loans by credit risk and vintage is the most meaningful presentation.
Non-Accrual Financing Receivables (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | March 31, 2020
​ | ​ | ​ | ​ | ​ | ​ | ​ | Amortized cost
​ | ​ | Beginning | ​ | Ending | ​ | of nonaccrual
​ | ​ | amortized cost | ​ | amortized cost | ​ | assets without
​ | ​ | on nonaccrual | ​ | on nonaccrual | ​ | a valuation
​ |  | status |  | status |  | allowance
​ | ​ | ​ | (in millions)
Commercial mortgage loans | ​ | $ | 5.0 | ​ | $ | 4.5 | ​ | $ | —
Residential mortgage loans |  | ​ | 6.8 |  | ​ | 6.9 |  | ​ | 0.8
Total |  | $ | 11.8 |  | $ | 11.4 |  | $ | 0.8
​ ​
​ | ​ | ​ | ​
​ |  | December 31, 2019 (1)
​ | ​ | (in millions)
Residential: | ​ | ​ | ​
First liens | ​ | $ | 8.8
Home equity | ​ |  | 3.0
Total | ​ | $ | 11.8
(1) | Prior to the implementation of authoritative guidance in 2020, commercial and residential mortgage loan non-accrual disclosures included information about classes of those mortgages. Beginning in 2020, we determined that total commercial and residential mortgage loans on non-accrual status is the most meaningful presentation.
Financing Receivables Aging (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | March 31, 2020
​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | Amortized
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | cost
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 90 days or | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 90 days or
​ | ​ | 30-59 days | ​ | 60-89 days | ​ | more past | ​ | Total past | ​ | ​ | ​ | ​ | ​ | ​ | ​ | more and
​ | ​ | past due | ​ | past due | ​ | due | ​ | due | ​ | Current | ​ | Total (1) | ​ | accruing
​ | ​ | (in millions)
Commercial mortgage loans | ​ | $ | 5.8 | ​ | $ | — | ​ | $ | 4.4 | ​ | $ | 10.2 | ​ | $ | 15,132.4 | ​ | $ | 15,142.6 | ​ | $ | —
Direct financing leases | ​ | ​ | 4.9 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 4.9 | ​ | ​ | 640.7 | ​ | ​ | 645.6 | ​ | ​ | —
Residential mortgage loans | ​ | ​ | 35.0 | ​ | ​ | 8.0 | ​ | ​ | 6.1 | ​ | ​ | 49.1 | ​ | ​ | 1,498.0 | ​ | ​ | 1,547.1 | ​ | ​ | 2.8
Total | ​ | $ | 45.7 | ​ | $ | 8.0 | ​ | $ | 10.5 | ​ | $ | 64.2 | ​ | $ | 17,271.1 | ​ | $ | 17,335.3 | ​ | $ | 2.8
​
(1) | No reinsurance recoverables were considered past due as of March 31, 2020.
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, 2019 (1)
​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | Recorded
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | investment
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 90 days or | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 90 days or
​ | ​ | 30-59 days | ​ | 60-89 days | ​ | more past | ​ | Total past | ​ | ​ | ​ | ​ | ​ | ​ | ​ | more and
​ | ​ | past due | ​ | past due | ​ | due | ​ | due | ​ | Current | ​ | Total loans | ​ | accruing
​ | ​ | (in millions)
Commercial-brick and mortar | ​ | $ | — | ​ | $ | — | ​ | $ | — | ​ | $ | — | ​ | $ | 14,856.7 | ​ | $ | 14,856.7 | ​ | $ | —
Commercial-CTL | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | 160.5 | ​ |  | 160.5 | ​ |  | —
Residential-first liens | ​ |  | 46.6 | ​ |  | 9.3 | ​ |  | 11.2 | ​ |  | 67.1 | ​ |  | 1,418.6 | ​ |  | 1,485.7 | ​ |  | 2.7
Residential-home equity | ​ |  | 0.8 | ​ |  | — | ​ |  | 0.3 | ​ |  | 1.1 | ​ |  | 9.9 | ​ |  | 11.0 | ​ |  | —
Total | ​ | $ | 47.4 | ​ | $ | 9.3 | ​ | $ | 11.5 | ​ | $ | 68.2 | ​ | $ | 16,445.7 | ​ | $ | 16,513.9 | ​ | $ | 2.7
(1) | Prior to the implementation of authoritative guidance in 2020, commercial and residential mortgage loan past due disclosures included information about classes of those mortgages. Beginning in 2020, we determined that aging for total commercial and residential mortgage loans is the most meaningful presentation.
Financing Receivables Valuation Allowance (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the three months ended March 31, 2020
​ | ​ | ​ | ​ | ​ | Direct | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Commercial | ​ | financing | ​ | ​ | Residential | Reinsurance | ​ | ​ | ​
​ |  | mortgage loans |  | leases |  | ​ | mortgage loans |  | recoverables |  | Total
​ | ​ | ​ | (in millions)
Beginning balance (1) | ​ | $ | 27.3 | ​ | $ | — | ​ | $ | 3.3 | ​ | $ | 2.5 | ​ | $ | 33.1
Provision (2) |  | ​ | 10.4 |  | ​ | 0.2 |  | ​ | 2.3 |  | ​ | — |  | ​ | 12.9
Charge-offs |  | ​ | — |  | ​ | — |  | ​ | (0.1) |  | ​ | — |  | ​ | (0.1)
Recoveries |  | ​ | — |  | ​ | — |  | ​ | 0.6 |  | ​ | — |  | ​ | 0.6
Ending balance |  | $ | 37.7 |  | $ | 0.2 |  | $ | 6.1 |  | $ | 2.5 |  | $ | 46.5
​ ​ ​ ​ ​ ​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Commercial |  | Residential |  | Total
​ | ​ | (in millions)
For the three months ended March 31, 2019 (3) | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Beginning balance | ​ | $ | 24.3 | ​ | $ | 3.1 | ​ | $ | 27.4
Provision | ​ |  | 0.4 | ​ |  | (0.8) | ​ |  | (0.4)
Charge-offs | ​ |  | — | ​ |  | (0.1) | ​ |  | (0.1)
Recoveries | ​ | ​ | — | ​ | ​ | 0.7 | ​ | ​ | 0.7
Ending balance | ​ | $ | 24.7 | ​ | $ | 2.9 | ​ | $ | 27.6
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Allowance ending balance by basis of impairment method: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Individually evaluated for impairment | ​ | $ | — | ​ | $ | 1.4 | ​ | $ | 1.4
Collectively evaluated for impairment | ​ | ​ | 24.7 | ​ | ​ | 1.5 | ​ | ​ | 26.2
Allowance ending balance | ​ | $ | 24.7 | ​ | $ | 2.9 | ​ | $ | 27.6
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Loan balance by basis of impairment method: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Individually evaluated for impairment | ​ | $ | — | ​ | $ | 8.1 | ​ | $ | 8.1
Collectively evaluated for impairment | ​ | ​ | 14,274.2 | ​ | ​ | 1,342.8 | ​ | ​ | 15,617.0
Loan ending balance | ​ | $ | 14,274.2 | ​ | $ | 1,350.9 | ​ | $ | 15,625.1
(1) | Upon adoption of authoritative guidance effective January 1, 2020, we updated accounting policies and methodology, adjusted the commercial and residential mortgage loan valuation allowance and established a valuation allowance for reinsurance recoverables. See Note 1, Nature of Operations and Significant Accounting Policies under the caption, "Recent Accounting Pronouncements" for further details.
(2) | During the three months ended March 31, 2020, the outbreak of COVID-19 adversely impacted global economic activity and contributed to significant volatility in financial markets. As a result, certain current and forecasted environmental factors management believes to be relevant were adjusted, resulting in an increase in the valuation allowance for commercial and residential mortgage loans and direct financing leases.
(3) | Prior to the implementation of authoritative guidance in 2020, only commercial and residential mortgage loans were included in the allowance rollforward and the allowance was based on either individual or collective evaluation.
Mortgage Loans Purchased and Sold (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the three months ended
​ | ​ | March 31,
​ |  | 2020 |  | 2019
​ | ​ | (in millions)
Commercial mortgage loans: |  | ​ |  |  | ​ |
Purchased | ​ | $ | 12.8 | ​ | $ | 12.9
Sold | ​ | ​ | 1.1 | ​ | ​ | 0.5
Residential mortgage loans: | ​ |  | ​ | ​ |  |
Purchased | ​ |  | 226.8 | ​ |  | 33.2
Sold | ​ |  | 24.9 | ​ |  | 10.9
Commercial Mortgage Loans by Geographic Distribution and Property Type Distribution (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | March 31, 2020 | ​ | December 31, 2019 |
​ |  | Amortized |  | Percent |  | Amortized |  | Percent |
​ | ​ | cost | ​ | of total | ​ | cost | ​ | of total |
​ | ​ | ($ in millions) |
Geographic distribution | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
New England | ​ | $ | 682.7 | ​ | 4.5 | % | $ | 613.9 | ​ | 4.1 | %
Middle Atlantic | ​ |  | 4,168.0 | ​ | 27.6 | ​ |  | 4,139.7 | ​ | 27.5 | ​
East North Central | ​ |  | 615.4 | ​ | 4.1 | ​ |  | 624.5 | ​ | 4.2 | ​
West North Central | ​ |  | 226.7 | ​ | 1.5 | ​ |  | 237.2 | ​ | 1.6 | ​
South Atlantic | ​ |  | 2,306.9 | ​ | 15.2 | ​ |  | 2,318.4 | ​ | 15.4 | ​
East South Central | ​ |  | 431.7 | ​ | 2.9 | ​ |  | 438.5 | ​ | 2.9 | ​
West South Central | ​ |  | 1,443.8 | ​ | 9.5 | ​ |  | 1,450.0 | ​ | 9.7 | ​
Mountain | ​ |  | 943.5 | ​ | 6.2 | ​ |  | 931.8 | ​ | 6.2 | ​
Pacific | ​ |  | 4,047.2 | ​ | 26.7 | ​ |  | 3,963.7 | ​ | 26.4 | ​
International | ​ |  | 276.7 | ​ | 1.8 | ​ |  | 299.5 | ​ | 2.0 | ​
Total | ​ | $ | 15,142.6 | ​ | 100.0 | % | $ | 15,017.2 | ​ | 100.0 | %
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Property type distribution | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Office | ​ | $ | 4,812.6 | ​ | 31.8 | % | $ | 4,887.1 | ​ | 32.6 | %
Retail | ​ |  | 1,954.4 | ​ | 12.9 | ​ |  | 2,052.6 | ​ | 13.7 | ​
Industrial | ​ |  | 2,335.2 | ​ | 15.4 | ​ |  | 2,268.5 | ​ | 15.1 | ​
Apartments | ​ |  | 5,522.0 | ​ | 36.5 | ​ |  | 5,246.9 | ​ | 34.9 | ​
Hotel | ​ |  | 90.0 | ​ | 0.6 | ​ |  | 90.8 | ​ | 0.6 | ​
Mixed use/other | ​ |  | 428.4 | ​ | 2.8 | ​ |  | 471.3 | ​ | 3.1 | ​
Total | ​ | $ | 15,142.6 | ​ | 100.0 | % | $ | 15,017.2 | ​ | 100.0 | %
Financial Assets Subject to Netting Agreements (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross amounts not offset in the | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | consolidated statements | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | of financial position | ​ | ​ | ​
​ | ​ | Gross amount | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | of recognized | ​ | Financial | ​ | Collateral | ​ | ​ | ​
​ |  | assets (1) |  | instruments (2) |  | received |  | Net amount
​ | ​ | (in millions)
March 31, 2020 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Derivative assets | ​ | $ | 616.2 | ​ | $ | (93.8) | ​ | $ | (517.5) | ​ | $ | 4.9
Reverse repurchase agreements | ​ | ​ | 9.7 | ​ | ​ | — | ​ | ​ | (9.7) | ​ | ​ | —
Total | ​ | $ | 625.9 | ​ | $ | (93.8) | ​ | $ | (527.2) | ​ | $ | 4.9
December 31, 2019 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Derivative assets | ​ | $ | 288.7 | ​ | $ | (88.4) | ​ | $ | (197.6) | ​ | $ | 2.7
Reverse repurchase agreements | ​ |  | 23.6 | ​ | ​ | — | ​ | ​ | (23.6) | ​ | ​ | —
Total | ​ | $ | 312.3 | ​ | $ | (88.4) | ​ | $ | (221.2) | ​ | $ | 2.7
(1) | The gross amount of recognized derivative and reverse repurchase agreement assets are reported with other investments and cash and cash equivalents, respectively, on the consolidated statements of financial position. The above excludes $1.4 million and $6.0 million of derivative assets as of March 31, 2020 and December 31, 2019, respectively, that are not subject to master netting agreements or similar agreements. The gross amounts of derivative and reverse repurchase agreement assets are not netted against offsetting liabilities for presentation on the consolidated statements of financial position.
(2) | Represents amount of offsetting derivative liabilities that are subject to an enforceable master netting agreement or similar agreement that are not netted against the gross derivative assets for presentation on the consolidated statements of financial position.
Financial Liabilities Subject to Netting Agreements (Table) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross amounts not offset in the | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | consolidated statements | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | of financial position | ​ | ​ | ​ |
​ | ​ | Gross amount | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | of recognized | ​ | Financial | ​ | Collateral | ​ | ​ | ​ |
​ |  | liabilities (1) |  | instruments (2) |  | pledged |  | Net amount |
​ | ​ | (in millions) |
March 31, 2020 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Derivative liabilities | ​ | $ | 203.7 | ​ | $ | (93.8) | ​ | $ | (92.9) | ​ | $ | 17.0 | ​
December 31, 2019 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Derivative liabilities | ​ | $ | 216.0 | ​ | $ | (88.4) | ​ | $ | (118.3) | ​ | $ | 9.3 | ​
(1) | The gross amount of recognized derivative liabilities is reported with other liabilities on the consolidated statements of financial position. The above excludes $596.9 million and $314.5 million of derivative liabilities as of March 31, 2020 and December 31, 2019, respectively, which are primarily embedded derivatives that are not subject to master netting agreements or similar agreements. The gross amounts of derivative liabilities are not netted against offsetting assets for presentation on the consolidated statements of financial position.
(2) | Represents amount of offsetting derivative assets that are subject to an enforceable master netting agreement or similar agreement that are not netted against the gross derivative liabilities for presentation on the consolidated statements of financial position.

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