Recent Accounting Pronouncements (Policies)	6 Months Ended
Jun. 30, 2018
Accounting Changes and Error Corrections [Abstract]
Variable Interest Entities	The Company accounts for its investment in these VIEs following the equity method of accounting. The carrying amounts of the Company’s equity investments are classified as other non-current assets on the accompanying consolidated balance sheets. The Company’s maximum exposure to loss as a result of its involvement with these VIEs is based on the Company’s capital contributions and the economic performance of the VIEs, and is equal to the carrying value of the Company’s investments which is the maximum loss the Company could be required to record in the consolidated statements of operations. See Note 3 for further discussion of these entities, including the carrying amounts of each investment.
Recent Accounting Pronouncements	In May 2014, the Financial Accounting Standards Board (“FASB”) issued ASC 606. ASC 606 supersedes existing industry specific revenue recognition guidance and increases disclosure requirements. The core principle of the new standard is for the recognition of revenue to depict the transfer of goods or services to customers in amounts that reflect the payment to which the company expects to be entitled in exchange for those goods or services. The Company adopted ASC 606 as of January 1, 2018 using the modified retrospective transition method applied to contracts that were not completed as of that date. Results for reporting periods beginning after January 1, 2018 are presented under the new revenue standard. Under the modified retrospective method, the Company recognizes the cumulative effect of initially applying the new revenue standard as an adjustment to the opening balance of retained earnings; however, no adjustment was required as a result of adopting the new revenue standard. The comparative information has not been restated and continues to be reported under the historic accounting standards in effect for those periods. The impact of the adoption of the new revenue standard is not expected to be material to the Company’s net income on an ongoing basis. In February 2016, the FASB issued ASU No. 2016-02, Leases. The standard updates the previous lease guidance by requiring the lessee to recognize a right-to-use asset and lease liability on the balance sheet for all leases with lease terms of more than 12 months. The accounting for lessors is largely unchanged. The guidance is effective for periods after December 15, 2018, with a modified retrospective approach to be used for implementation. The Company will not early adopt this standard, and will apply the revised lease rules for its interim and annual reporting periods starting January 1, 2019. The Company is in the process of evaluating the impact of this guidance on its consolidated financial statements and related disclosures by performing an impact assessment to analyze the population of arrangements that meet the definition of a lease under the new standard. This analysis could result in an impact to the Company's financial statements; however, that impact is currently not known. The Company is also in the process of selecting a lease accounting software solution to support lease portfolio management and accounting and disclosures for the new standard. Additionally, in January 2018, the FASB issued ASU No. 2018-01, Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842. The amendments in this update provide an optional transition to not evaluate existing or expired land easements that were not previously accounted for under current leases guidance in Topic 840. An entity that elects this practical expedient should evaluate new or modified land easements beginning at the date of adoption. An entity that does not elect this practical expedient should evaluate all existing or expired land easements in connection with the adoption of the new lease requirement in Topic 842 to assess whether they meet the definition of a lease. The Company is currently evaluating this guidance to determine whether or not to make use of this practical expedient. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments. This ASU amends guidance on reporting credit losses for assets held at amortized cost basis and available for sale debt securities. For assets held at amortized cost basis, this ASU eliminates the probable initial recognition threshold in current GAAP and instead, requires an entity to reflect its current estimate of all expected credit losses. The amendments affect loans, debt securities, trade receivables, net investments in leases, off balance sheet credit exposure, reinsurance receivables and any other financial assets not excluded from the scope that have the contractual right to receive cash. The guidance is effective for periods after December 15, 2019, with early adoption permitted. The Company is currently evaluating the impact this standard will have on its financial statements and related disclosures and does not anticipate it to have a material effect. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments. This ASU clarifies how certain cash receipts and cash payments should be classified and presented in the statement of cash flows. The Company adopted this standard in the first quarter of 2018 and has made an accounting policy election to classify distributions received from equity method investees using the nature of the distribution approach, which classifies distributions received from investees as either cash inflows from operating activities or cash inflows from investing activities in the statement of cash flows based on the nature of the activities of the investee that generated the distribution. The impact of adopting this ASU was not material to prior periods presented. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash This ASU requires that amounts generally described as restricted cash and restricted cash equivalents be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period amounts shown on the statement of cash flows and to provide a reconciliation of the totals in the statement of cash flows to the related captions in the balance sheet when the cash, cash equivalents, restricted cash, and restricted cash equivalents are presented in more than one line item on the balance sheet. The Company adopted this standard in the first quarter of 2018 using the retrospective transition method. The adoption of this standard had no impact on the statement of cash flows for the six months ended June 30, 2018 and resulted in the addition of $185.0 million of restricted cash to the beginning cash balance and an increase to net cash used in investing activities by the same amount on the statement of cash flows for the six months ended June 30, 2017. In January 2017, the FASB issued ASU No. 2017-01, Clarifying the Definition of a Business. Under the current business combination guidance, there are three elements of a business: inputs, processes and outputs. The revised guidance adds an initial screen test to determine if substantially all of the fair value of the gross assets acquired is concentrated in a single asset or group of similar assets. If that screen is met, the set of assets is not a business. The new framework also specifies the minimum required inputs and processes necessary to be a business. The Company adopted this standard in the first quarter of 2018 with no significant effect on its financial statements or related disclosures. In February 2018, the FASB issued ASU No. 2018-02, Income statement - Reporting Comprehensive Income (Topic 220) - Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, which allows a reclassification from accumulated other comprehensive income to retained earnings for standard tax effects resulting from the Tax Cuts and Jobs Act of 2017. The amendment will be effective for reporting periods beginning after December 15, 2018, and early adoption is permitted. The Company is currently assessing the impact of the ASU on its consolidated financial statements and related disclosures.

In May 2014, the Financial Accounting Standards Board (“FASB”) issued ASC 606. ASC 606 supersedes existing industry specific revenue recognition guidance and increases disclosure requirements. The core principle of the new standard is for the recognition of revenue to depict the transfer of goods or services to customers in amounts that reflect the payment to which the company expects to be entitled in exchange for those goods or services. The Company adopted ASC 606 as of January 1, 2018 using the modified retrospective transition method applied to contracts that were not completed as of that date. Results for reporting periods beginning after January 1, 2018 are presented under the new revenue standard. Under the modified retrospective method, the Company recognizes the cumulative effect of initially applying the new revenue standard as an adjustment to the opening balance of retained earnings; however, no adjustment was required as a result of adopting the new revenue standard. The comparative information has not been restated and continues to be reported under the historic accounting standards in effect for those periods. The impact of the adoption of the new revenue standard is not expected to be material to the Company’s net income on an ongoing basis.

In February 2016, the FASB issued ASU No. 2016-02, Leases. The standard updates the previous lease guidance by requiring the lessee to recognize a right-to-use asset and lease liability on the balance sheet for all leases with lease terms of more than 12 months. The accounting for lessors is largely unchanged. The guidance is effective for periods after December 15, 2018, with a modified retrospective approach to be used for implementation. The Company will not early adopt this standard, and will apply the revised lease rules for its interim and annual reporting periods starting January 1, 2019. The Company is in the process of evaluating the impact of this guidance on its consolidated financial statements and related disclosures by performing an impact assessment to analyze the population of arrangements that meet the definition of a lease under the new standard. This analysis could result in an impact to the Company's financial statements; however, that impact is currently not known. The Company is also in the process of selecting a lease accounting software solution to support lease portfolio management and accounting and disclosures for the new standard.

Additionally, in January 2018, the FASB issued ASU No. 2018-01, Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842. The amendments in this update provide an optional transition to not evaluate existing or expired land easements that were not previously accounted for under current leases guidance in Topic 840. An entity that elects this practical expedient should evaluate new or modified land easements beginning at the date of adoption. An entity that does not elect this practical expedient should evaluate all existing or expired land easements in connection with the adoption of the new lease requirement in Topic 842 to assess whether they meet the definition of a lease. The Company is currently evaluating this guidance to determine whether or not to make use of this practical expedient.

In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments. This ASU amends guidance on reporting credit losses for assets held at amortized cost basis and available for sale debt securities. For assets held at amortized cost basis, this ASU eliminates the probable initial recognition threshold in current GAAP and instead, requires an entity to reflect its current estimate of all expected credit losses. The amendments affect loans, debt securities, trade receivables, net investments in leases, off balance sheet credit exposure, reinsurance receivables and any other financial assets not excluded from the scope that have the contractual right to receive cash. The guidance is effective for periods after December 15, 2019, with early adoption permitted. The Company is currently evaluating the impact this standard will have on its financial statements and related disclosures and does not anticipate it to have a material effect.

In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments. This ASU clarifies how certain cash receipts and cash payments should be classified and presented in the statement of cash flows. The Company adopted this standard in the first quarter of 2018 and has made an accounting policy election to classify distributions received from equity method investees using the nature of the distribution approach, which classifies distributions received from investees as either cash inflows from operating activities or cash inflows from investing activities in the statement of cash flows based on the nature of the activities of the investee that generated the distribution. The impact of adopting this ASU was not material to prior periods presented.

In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash This ASU requires that amounts generally described as restricted cash and restricted cash equivalents be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period amounts shown on the statement of cash flows and to provide a reconciliation of the totals in the statement of cash flows to the related captions in the balance sheet when the cash, cash equivalents, restricted cash, and restricted cash equivalents are presented in more than one line item on the balance sheet. The Company adopted this standard in the first quarter of 2018 using the retrospective transition method. The adoption of this standard had no impact on the statement of cash flows for the six months ended June 30, 2018 and resulted in the addition of $185.0 million of restricted cash to the beginning cash balance and an increase to net cash used in investing activities by the same amount on the statement of cash flows for the six months ended June 30, 2017.

In January 2017, the FASB issued ASU No. 2017-01, Clarifying the Definition of a Business. Under the current business combination guidance, there are three elements of a business: inputs, processes and outputs. The revised guidance adds an initial screen test to determine if substantially all of the fair value of the gross assets acquired is concentrated in a single asset or group of similar assets. If that screen is met, the set of assets is not a business. The new framework also specifies the minimum required inputs and processes necessary to be a business. The Company adopted this standard in the first quarter of 2018 with no significant effect on its financial statements or related disclosures.

In February 2018, the FASB issued ASU No. 2018-02, Income statement - Reporting Comprehensive Income (Topic 220) - Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, which allows a reclassification from accumulated other comprehensive income to retained earnings for standard tax effects resulting from the Tax Cuts and Jobs Act of 2017. The amendment will be effective for reporting periods beginning after December 15, 2018, and early adoption is permitted. The Company is currently assessing the impact of the ASU on its consolidated financial statements and related disclosures.