| Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] |
The following tables summarize the Company's assets and liabilities that are measured at fair value on a recurring basis (in thousands): | | | | | | | | | | | | | | | | | | | | Fair Value Measurement at Reporting Date Using | Description | June 30, 2014 | | Quoted Prices in Active Markets for
Identical Assets
(Level 1) | | Significant Other
Observable
Inputs
(Level 2) | | Significant
Unobservable
Inputs
(Level 3) | Assets: | | | | | | | | Cash equivalents | $ | 500,558 |
| | $ | 500,558 |
| | $ | — |
| | $ | — |
| Available-for-sale securities: | | | | | | | | Convertible debt securities | $ | 2,630 |
| | $ | — |
| | $ | — |
| | $ | 2,630 |
| Redeemable preferred shares | $ | 4,544 |
| | $ | — |
| | $ | — |
| | $ | 4,544 |
| | | | | | | | | Liabilities: | | | | | | | | Contingent consideration | $ | 4,006 |
| | $ | — |
| | $ | — |
| | $ | 4,006 |
|
| | | | | | | | | | | | | | | | | | | | Fair Value Measurement at Reporting Date Using | Description | December 31, 2013 | | Quoted Prices in Active Markets for
Identical Assets
(Level 1) | | Significant Other
Observable
Inputs
(Level 2) | | Significant
Unobservable
Inputs
(Level 3) | Assets: | | | | | | | | Cash equivalents | $ | 585,514 |
| | $ | 585,514 |
| | $ | — |
| | $ | — |
| Available-for-sale securities: | | | | | | | | Convertible debt securities | $ | 3,174 |
| | $ | — |
| | $ | — |
| | $ | 3,174 |
| Redeemable preferred shares | $ | — |
| | $ | — |
| | $ | — |
| | $ | — |
| | | | | | | | | Liabilities: | | | | | | | | Contingent consideration | $ | 606 |
| | $ | — |
| | $ | — |
| | $ | 606 |
|
|
| Fair Value, Assets and Liabilities, Reconciliation of Level 3 Inputs [Table Text Block] |
The following table provides a roll-forward of the fair value of recurring Level 3 fair value measurements for the three and six months ended June 30, 2014 and 2013 (in thousands): | | | | | | | | | | | | | | | | | | Three Months Ended June 30, | | Six Months Ended June 30, | | 2014 | | 2013 | | 2014 | | 2013 | Assets | | | | | | | | Available-for-sale securities | | | | | | | | Convertible debt securities: | | | | | | | | Beginning Balance | $ | 2,693 |
| | $ | 3,341 |
| | $ | 3,174 |
| | $ | 3,087 |
| Total (losses) gains included in other comprehensive (loss) income | (63 | ) | | (108 | ) | | (544 | ) | | 146 |
| Ending Balance | $ | 2,630 |
| | $ | 3,233 |
| | $ | 2,630 |
| | $ | 3,233 |
| Unrealized (losses) gains still held(1) | $ | (63 | ) | | $ | (108 | ) | | $ | (544 | ) | | $ | 146 |
| Redeemable preferred shares(2): | | | | | | | | Beginning Balance | $ | 4,599 |
| | $ | 42,539 |
| | $ | — |
| | $ | 42,539 |
| Purchase of redeemable preferred shares | — |
| | — |
| | 4,599 |
| | — |
| Total (losses) gains included in other comprehensive (loss) income | (55 | ) | | — |
| | (55 | ) | | — |
| Ending Balance | $ | 4,544 |
| | $ | 42,539 |
| | $ | 4,544 |
| | $ | 42,539 |
| Unrealized (losses) gains still held(1) | $ | (55 | ) | | $ | — |
| | $ | (55 | ) | | $ | — |
| | | | | | | | | Liabilities | | | | | | | | Contingent Consideration: | | | | | | | | Beginning Balance | $ | — |
| | $ | 7,699 |
| | $ | 606 |
| | $ | 7,601 |
| Issuance of contingent consideration in connection with acquisitions | 4,006 |
| | — |
| | 4,006 |
| | 30 |
| Settlements of contingent consideration liabilities | — |
| | (30 | ) | | (424 | ) | | (30 | ) | Reclass to non-fair value liabilities when no longer contingent | — |
| | — |
| | (143 | ) | | — |
| Total (gains) losses included in earnings(3) | — |
| | (815 | ) | | (39 | ) | | (747 | ) | Ending Balance | $ | 4,006 |
| | $ | 6,854 |
| | $ | 4,006 |
| | $ | 6,854 |
| Unrealized (gains) losses still held(1) | $ | — |
| | $ | (815 | ) | | $ | — |
| | $ | (747 | ) |
| | (1) | Represents the unrealized losses or gains recorded in earnings or other comprehensive (loss) income during the period for assets and liabilities classified as Level 3 that are still held (or outstanding) at the end of the period. |
| | (2) | For the three and six months ending June 30, 2013, the Company's investments in Life Media Limited (F-tuan) preferred shares were previously classified as cost method investments and have been reclassified to the available-for-sale category in this table. The balance as of June 30, 2013 represents the Company’s investments in F-tuan preferred shares, which were written down to zero through an other-than-temporary impairment charge as of December 31, 2013 and continue to have an estimated fair value of zero as of June 30, 2014. The $4.5 million balance as of June 30, 2014 represents the Company's investment in the preferred shares of an online home services company during the current period, as described in Note 4 "Investments." |
| | (3) | Changes in the fair value of contingent consideration liabilities are classified within "Acquisition-related expense (benefit), net" on the condensed consolidated statements of operations. |
|
| Fair Value of Financial Assets and Liabilities not Measured at Fair Value [Table Text Block] |
The following table presents the carrying amounts and fair values of financial instruments that are not carried at fair value in the condensed consolidated financial statements (in thousands): | | | | | | | | | | | | | | | | | | | | June 30, 2014 | | December 31, 2013 | | | Carrying Amount | | Fair Value | | Carrying Amount | | Fair Value | Cost method investments | | $ | 15,092 |
| | $ | 17,593 |
| | $ | 15,788 |
| | $ | 15,573 |
|
|