Commitments and Contingencies (Details 4) (Pacchia case, USD $)	0 Months Ended	12 Months Ended
	Nov. 19, 2014	Dec. 31, 2014
Proposed settlement agreement related to the Purchase Transaction and Private Sale
Litigation Settlement [Line Items]
Settlement fund	$ 275,000,000
Proposed settlement agreement related to the Purchase Transaction and Private Sale | Payment to plaintiff's attorney
Litigation Settlement [Line Items]
Payments from settlement fund	72,500,000
Proposed settlement agreement related to the Purchase Transaction and Private Sale | Payment to the Company to be recorded within Shareholders' Equity
Litigation Settlement [Line Items]
Payments from settlement fund	202,500,000
Objections to settlement agreement | Special award to lead plaintiff
Litigation Settlement [Line Items]
Payments from settlement fund		50,000
Additional requests filed | Reallocation of plaintiff's attorney's fees
Litigation Settlement [Line Items]
Payments from settlement fund		$ 7,500,000