0000001 - Document - Cover link:presentationLink link:calculationLink link:definitionLink 0000002 - Statement - Statements of Net Assets Available for Benefits link:presentationLink link:calculationLink link:definitionLink 0000003 - Statement - Statement of Changes in Net Assets Available for Benefits link:presentationLink link:calculationLink link:definitionLink 0000004 - Disclosure - Description of the Plan link:presentationLink link:calculationLink link:definitionLink 0000005 - Disclosure - Summary of significant accounting policies link:presentationLink link:calculationLink link:definitionLink 0000006 - Disclosure - Fair value measurements link:presentationLink link:calculationLink link:definitionLink 0000007 - Disclosure - Investment program link:presentationLink link:calculationLink link:definitionLink 0000008 - Disclosure - Synthetic GICs link:presentationLink link:calculationLink link:definitionLink 0000009 - Disclosure - Derivative instruments link:presentationLink link:calculationLink link:definitionLink 0000010 - Disclosure - Transactions with parties in interest link:presentationLink link:calculationLink link:definitionLink 0000011 - Disclosure - Tax status and federal income taxes link:presentationLink link:calculationLink link:definitionLink 0000012 - Disclosure - Commitments and contingencies link:presentationLink link:calculationLink link:definitionLink 0000013 - Disclosure - Risks and uncertainties link:presentationLink link:calculationLink link:definitionLink 0000014 - Disclosure - Plan termination link:presentationLink link:calculationLink link:definitionLink 0000015 - Disclosure - Off-cycle payroll contributions link:presentationLink link:calculationLink link:definitionLink 0000016 - Disclosure - Subsequent events link:presentationLink link:calculationLink link:definitionLink 0000017 - Disclosure - Schedule of Assets (Held at End of Year) link:presentationLink link:calculationLink link:definitionLink 0000018 - Disclosure - Schedule of Assets (Acquired and Disposed of Within Year) link:presentationLink link:calculationLink link:definitionLink 0000019 - Disclosure - Schedule of Loans or Fixed Income Obligations in Default or Classified as Uncollectable link:presentationLink link:calculationLink link:definitionLink 0000020 - Disclosure - Schedule of Delinquent Participant Contributions link:presentationLink link:calculationLink link:definitionLink 0000021 - Disclosure - Summary of significant accounting policies (Policies) link:presentationLink link:calculationLink link:definitionLink 0000022 - Disclosure - Summary of significant accounting policies (Tables) link:presentationLink link:calculationLink link:definitionLink 0000023 - Disclosure - Fair value measurements (Tables) link:presentationLink link:calculationLink link:definitionLink 0000024 - Disclosure - Synthetic GICs (Tables) link:presentationLink link:calculationLink link:definitionLink 0000025 - Disclosure - Derivative instruments (Tables) link:presentationLink link:calculationLink link:definitionLink 0000026 - Disclosure - Transactions with parties in interest (Tables) link:presentationLink link:calculationLink link:definitionLink 0000027 - Disclosure - Description of the Plan (Details) link:presentationLink link:calculationLink link:definitionLink 0000028 - Disclosure - Summary of significant accounting policies - Reconciliation of Net Assets Available for Benefits per the Financial Statements to Form 5500 (Details) link:presentationLink link:calculationLink link:definitionLink 0000029 - Disclosure - Summary of significant accounting policies - Reconciliation of Benefits Paid to Participants per the Financial Statements to Form 5500 (Details) link:presentationLink link:calculationLink link:definitionLink 0000030 - Disclosure - Fair value measurements (Details) link:presentationLink link:calculationLink link:definitionLink 0000031 - Disclosure - Investment program (Details) link:presentationLink link:calculationLink link:definitionLink 0000032 - Disclosure - Synthetic GICs (Details) link:presentationLink link:calculationLink link:definitionLink 0000033 - Disclosure - Derivative instruments - Notional Amount (Details) link:presentationLink link:calculationLink link:definitionLink 0000034 - Disclosure - Derivative instruments - Gross Fair Value of Derivatives Receivable (Details) link:presentationLink link:calculationLink link:definitionLink 0000035 - Disclosure - Derivative instruments - Derivatives Gains and Losses (Details) link:presentationLink link:calculationLink link:definitionLink 0000036 - Disclosure - Derivative instruments - Credit Risk (Details) link:presentationLink link:calculationLink link:definitionLink 0000037 - Disclosure - Derivative instruments - Protection Sold Credit Derivatives (Details) link:presentationLink link:calculationLink link:definitionLink 0000038 - Disclosure - Transactions with parties in interest (Details) link:presentationLink link:calculationLink link:definitionLink 0000039 - Disclosure - Schedule of Assets (Held at End of Year) (Details) link:presentationLink link:calculationLink link:definitionLink 0000039 - Disclosure - Schedule of Assets (Held at End of Year) (Details) link:presentationLink link:calculationLink link:definitionLink 0000040 - Disclosure - Schedule of Assets (Acquired and Disposed of Within Year) (Details) link:presentationLink link:calculationLink link:definitionLink 0000040 - Disclosure - Schedule of Assets (Acquired and Disposed of Within Year) (Details) link:presentationLink link:calculationLink link:definitionLink 0000041 - Disclosure - Schedule of Loans or Fixed Income Obligations in Default or Classified as Uncollectable (Details) link:presentationLink link:calculationLink link:definitionLink 0000041 - Disclosure - Schedule of Loans or Fixed Income Obligations in Default or Classified as Uncollectable (Details) link:presentationLink link:calculationLink link:definitionLink 0000042 - Disclosure - Schedule of Delinquent Participant Contributions (Details) link:presentationLink link:calculationLink link:definitionLink