Business Combination	3 Months Ended
Mar. 31, 2019
Business Combinations [Abstract]
Business Combination	Business Combination On July 31, 2018, we acquired a 66.7% equity stake in Silversea Cruise Holding Ltd. ("Silversea Cruises"), an ultra-luxury and expedition cruise line with nine ships, from Silversea Cruises Group Ltd. ("SCG"). Silversea Cruises enhances our presence in the ultra-luxury and expedition markets and provides us with an opportunity to drive long-term capacity growth in these markets. The purchase price consisted of $1.02 billion in cash, net of assumed liabilities, and contingent consideration that can range from zero up to a maximum of approximately 472,000 shares of our common stock, and is payable upon achievement of certain 2019-2020 performance metrics by Silversea Cruises. The fair value of the contingent consideration at the acquisition date was $44.0 million and is recorded within Other long-term liabilities in our consolidated balance sheets. Changes in the fair value of the contingent consideration are recorded in our results of operations, if any, in the period of the change. Refer to Note 14. Fair Value Measurements and Derivative Instruments for further information on the valuation of the contingent consideration. To finance a portion of the purchase price, we drew in full on a $700 million unsecured credit agreement and the remainder of the transaction consideration was financed through the use of our revolving credit facilities. We have accounted for this transaction under the provisions of ASC 805, Business Combinations. The purchase price for the Silversea Cruises acquisition was allocated based on estimates of the fair value of assets acquired and liabilities assumed at the acquisition date, with the excess allocated to goodwill. Goodwill is not deductible for tax purposes and consisted primarily of the opportunity to expand our cruise operations in strategic growth areas. For reporting purposes, we include Silversea Cruises’ results of operations on a three-month reporting lag from October 1, 2018 through December 31, 2018. We have included Silversea Cruises' balance sheet as of December 31, 2018 in our consolidated balance sheet as of March 31, 2019. Refer to Note 1. General for further information on this three-month reporting lag. Our purchase price allocation was final as of March 31, 2019. There were no measurement period adjustments recorded during the quarter ended March 31, 2019. Pro-forma financial results relating to the Silversea Cruises acquisition are not presented, as this acquisition was not material to our consolidated results of operations.

Business Combination

On July 31, 2018, we acquired a 66.7% equity stake in Silversea Cruise Holding Ltd. ("Silversea Cruises"), an ultra-luxury and expedition cruise line with nine ships, from Silversea Cruises Group Ltd. ("SCG"). Silversea Cruises enhances our presence in the ultra-luxury and expedition markets and provides us with an opportunity to drive long-term capacity growth in these markets.

The purchase price consisted of $1.02 billion in cash, net of assumed liabilities, and contingent consideration that can range from zero up to a maximum of approximately 472,000 shares of our common stock, and is payable upon achievement of certain 2019-2020 performance metrics by Silversea Cruises. The fair value of the contingent consideration at the acquisition date was $44.0 million and is recorded within Other long-term liabilities in our consolidated balance sheets. Changes in the fair value of the contingent consideration are recorded in our results of operations, if any, in the period of the change. Refer to Note 14. Fair Value Measurements and Derivative Instruments for further information on the valuation of the contingent consideration.

To finance a portion of the purchase price, we drew in full on a $700 million unsecured credit agreement and the remainder of the transaction consideration was financed through the use of our revolving credit facilities.

We have accounted for this transaction under the provisions of ASC 805, Business Combinations. The purchase price for the Silversea Cruises acquisition was allocated based on estimates of the fair value of assets acquired and liabilities assumed at the acquisition date, with the excess allocated to goodwill. Goodwill is not deductible for tax purposes and consisted primarily of the opportunity to expand our cruise operations in strategic growth areas.

For reporting purposes, we include Silversea Cruises’ results of operations on a three-month reporting lag from October 1, 2018 through December 31, 2018. We have included Silversea Cruises' balance sheet as of December 31, 2018 in our consolidated balance sheet as of March 31, 2019. Refer to Note 1. General for further information on this three-month reporting lag.

Our purchase price allocation was final as of March 31, 2019. There were no measurement period adjustments recorded during the quarter ended March 31, 2019.

Pro-forma financial results relating to the Silversea Cruises acquisition are not presented, as this acquisition was not material to our consolidated results of operations.