Fair Value Measurement of Assets and Liabilities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Fair Value Disclosure, additional details
Funds receivable and customer accounts	$ 9,648	$ 9,260
Long-Term Investment [Member]
Fair Value Disclosure, additional details
Cost and equity method investments included in long-term investments	357	269
Foreign Government Debt Securities [Member] | Short-term Investments [Member]
Fair Value Disclosure, additional details
Funds receivable and customer accounts	3,458
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Cash and cash equivalents	4,415	4,494
Financial assets	16,171	17,328
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	3,429	4,531
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Long-Term Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	4,848	4,696
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Other Current Assets
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Derivative assets	21	44
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Other Current Liabilities
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Derivatives liabilities	119	151
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Restricted Cash [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	19	17
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	2,620	3,529
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Long-Term Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	4,611	4,445
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Foreign Government Debt Securities [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	9	43
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Foreign Government Debt Securities [Member] | Long-Term Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	237	251
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Bank Time Deposits [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments		49
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring [Member] | Equity Securities [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	781	893
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Cash and cash equivalents	4,355	4,159
Financial assets	5,155	5,069
Fair Value Disclosure, additional details
Funds receivable and customer accounts	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	800	910
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Long-Term Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Other Current Assets
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Derivative assets	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Other Current Liabilities
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Derivatives liabilities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Restricted Cash [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	19	17
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Long-Term Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Foreign Government Debt Securities [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Foreign Government Debt Securities [Member] | Long-Term Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Bank Time Deposits [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments		0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring [Member] | Equity Securities [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	781	893
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Cash and cash equivalents	60	335
Financial assets	11,016	12,259
Fair Value Disclosure, additional details
Funds receivable and customer accounts	3,458
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	2,629	3,621
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Long-Term Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	4,848	4,696
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Other Current Assets
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Derivative assets	21	44
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Other Current Liabilities
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Derivatives liabilities	119	151
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Restricted Cash [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	0	0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	2,620	3,529
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Long-Term Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	4,611	4,445
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Foreign Government Debt Securities [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	9	43
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Foreign Government Debt Securities [Member] | Long-Term Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	237	251
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Bank Time Deposits [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments		49
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring [Member] | Equity Securities [Member] | Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Investments	0	0
Bank Time Deposits [Member]
Fair Value Disclosure, additional details
Held-to-maturity Securities, Current	$ 6	$ 6