Long-term Debt - Additional Information (Details) |
3 Months Ended | 6 Months Ended | |||||||
|---|---|---|---|---|---|---|---|---|---|
|
Apr. 04, 2019
$ / shares
|
Jun. 30, 2019
USD ($)
$ / shares
|
Mar. 31, 2019
$ / shares
|
Dec. 31, 2018
USD ($)
$ / shares
|
Sep. 30, 2018
$ / shares
|
Jun. 30, 2018
USD ($)
$ / shares
|
Mar. 31, 2018
$ / shares
|
Jun. 30, 2019
USD ($)
$ / shares
|
Jun. 30, 2018
USD ($)
|
|
| Debt Instrument [Line Items] | |||||||||
| Principal, net of issuance costs | $ 740,000,000 | $ 835,000,000 | $ 740,000,000 | ||||||
| Dividends declared per share (in usd per share) | $ / shares | $ 0.335 | $ 0.335 | $ 0.330 | $ 0.330 | $ 0.330 | $ 0.330 | |||
| Total interest expense | $ 14,869,000 | $ 19,033,000 | 30,300,000 | $ 37,744,000 | |||||
| Convertible Senior Notes [Member] | 4.125% Convertible Senior Notes Due September 1, 2022 [Member] | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Principal | 150,000,000 | $ 150,000,000 | 150,000,000 | ||||||
| Principal, net of issuance costs | $ 145,000,000 | $ 145,000,000 | |||||||
| Interest rate | 4.125% | 4.125% | |||||||
| Conversion rate of shares for each $1,000 principal amount of convertible notes | 36.7179 | ||||||||
| Adjustment for dividends declared (in usd per share) | $ / shares | $ 0.335 | ||||||||
| Conversion price per share (in usd per share) | $ / shares | $ 27.23 | ||||||||
| Redemption price, percentage | 100.00% | ||||||||
| Total interest expense | $ 2,000,000 | $ 2,000,000 | $ 4,000,000 | $ 4,000,000 | |||||
| X | ||||||||||
- Definition Adjustment for dividends declared minimum. No definition available.
|
| X | ||||||||||
- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The price per share of the conversion feature embedded in the debt instrument. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition 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. No definition available.
|
| X | ||||||||||
- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of the cost of borrowed funds accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|