The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Percentage of principal amount of debt redeemed.

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Gross amount of debt extinguished.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Number of shares issued during the period as a result of the conversion of convertible securities.

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Financing Arrangements - Senior Notes (Details 3)		1 Months Ended			6 Months Ended	12 Months Ended
Financing Arrangements - Senior Notes (Details 3)	May. 07, 2015 USD ($)	Nov. 30, 2014 USD ($)	Sep. 30, 2011 USD ($)	Feb. 29, 2004 USD ($)	Jun. 30, 2015 USD ($) shares	Dec. 31, 2015	Dec. 31, 2014 USD ($) shares	Dec. 31, 2013
3.5% Senior Notes
Financing Arrangements
Debt issued		$ 500,000,000
Interest rate (as a percent)		3.50%				3.50%	3.50%
Proceeds from issuance of notes, net of underwriting discounts		$ 491,000,000
3.5% Senior Notes \| On or after September 15, 2024
Financing Arrangements
Redemption price at which debt may be redeemed (as a percent)						100.00%
3.5% Senior Notes \| Change of control triggering event
Financing Arrangements
Redemption price at which debt may be redeemed (as a percent)						101.00%
3.5% Senior Notes \| Minimum \| Prior to September 15, 2024
Financing Arrangements
Redemption price at which debt may be redeemed (as a percent)						100.00%
3.375% Senior Notes
Financing Arrangements
Debt issued			$ 500,000,000
Interest rate (as a percent)			3.375%			3.375%	3.375%
Proceeds from issuance of notes, net of underwriting discounts			$ 492,000,000
3.375% Senior Notes \| Change of control triggering event
Financing Arrangements
Redemption price at which debt may be redeemed (as a percent)						101.00%
3.375% Senior Notes \| Minimum
Financing Arrangements
Redemption price at which debt may be redeemed (as a percent)						100.00%
1.5% Convertible Senior Notes due February 15, 2024
Financing Arrangements
Debt issued				$ 330,000,000
Interest rate (as a percent)				1.50%			1.50%	1.50%
Proceeds from issuance of notes, net of underwriting discounts				$ 323,000,000
Debt conversion, amount of original debt					$ 8,000,000
Stock issued in connection with conversion of debt (in shares) \| shares					167,674		1,750
Conversion ratio per $1,000 principal amount of Notes					0.0370997
Remaining outstanding debt redeemed	$ 10,000,000
Redemption price (as a percent)	100.00%
1.5% Convertible Senior Notes due February 15, 2024 \| Maximum
Financing Arrangements
Remaining outstanding debt redeemed							$ 100,000